Grade 10 Physical Sciences Chemistry — Northern Cape practice
Notes
Answer every question. Show the formula, the substitution, and the answer with units. Calculators allowed. These are original practice papers in the style of the province, not a copy of a department PDF.
90 min · 83 Marks · 30 questions
Learn the paper in the app: notes, a marks breakdown, the formula you need, and the board working. You do not need to download it.
A learner in Kimberley dissolves salt in water until it looks clear. The salt water is a
Notes: A learner in Kimberley dissolves salt in water until it looks clear. The salt water is a
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: A learner in Kimberley dissolves salt in water until it looks clear. The salt water is a
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: The salt water is a. Circle that word — that is the missing variable.
Find
We are required to find: The salt water is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: One phase, salt dissolved: a solution is a homogeneous mixture. Then substitute the given, one line at a time, to get The salt water is a.
In other words — as if you have never seen this before
One phase, salt dissolved: a solution is a homogeneous mixture.
2. What do we already know?
A learner in Kimberley dissolves salt in water until it looks clear. The salt water is a
3. Which method — and why this one?
One phase, salt dissolved: a solution is a homogeneous mixture.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: The salt water is a. Circle that word — that is the missing variable.
Find: We are required to find: The salt water is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: One phase, salt dissolved: a solution is a homogeneous mixture. Then substitute the given, one line at a time, to get The salt water is a.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
A learner in Kimberley dissolves salt in water until it looks clear. The salt water is a
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
One phase, salt dissolved: a solution is a homogeneous mixture.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
One phase, salt dissolved: a solution is a homogeneous mixture.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
homogeneous mixture
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
homogeneous mixture
Copy onto your answer sheet — in this order
Answer: homogeneous mixture
6. Check it like a marker
One phase, salt dissolved: a solution is a homogeneous mixture.
7. A trap first-timers fall into
compound
1.2 · 4 Marks
Sodium-27. Z = 11. Neutrons?
Notes: Sodium-27. Z = 11. Neutrons?
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Sodium-27. Z = 11. Neutrons?
Before any working — hunt first
Given
Numbers and units already in the sentence: 27 · 11. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Neutrons. Circle that word — that is the missing variable.
Find
We are required to find: Neutrons. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: N = A − Z = 27 − 11 = 16. Then substitute the given, one line at a time, to get Neutrons.
In other words — as if you have never seen this before
N=A−Z=27−11=16.
2. What do we already know?
Sodium-27. Z = 11. Neutrons?
3. Which method — and why this one?
N=A−Z=27−11=16.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 27 · 11. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Neutrons. Circle that word — that is the missing variable.
Find: We are required to find: Neutrons. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: N = A − Z = 27 − 11 = 16. Then substitute the given, one line at a time, to get Neutrons.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Sodium-27. Z = 11. Neutrons?
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
N=A−Z=27−11=16.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
N=A−Z=27−11=16.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
16
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
16
Copy onto your answer sheet — in this order
Answer: 16
6. Check it like a marker
N=A−Z=27−11=16.
7. A trap first-timers fall into
11
1.3 · 6 Marks
Mass of 0.6 mol of CO₂. M = 44 g·mol⁻¹.
Notes: Mass of 0.6 mol of CO₂. M = 44 g·mol⁻¹.
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Mass of 0.6 mol of CO₂. M = 44 g·mol⁻¹.
Before any working — hunt first
Given
Numbers and units already in the sentence: 0.6 mol · 44 g·mol⁻¹. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: M = 44 g·mol⁻¹. Circle that word — that is the missing variable.
Find
We are required to find: M = 44 g·mol⁻¹. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: m = nM = 0. Then substitute the given, one line at a time, to get M = 44 g·mol⁻¹.
In other words — as if you have never seen this before
m=nM=0.6×44=26.4 g.
2. What do we already know?
Mass of 0.6 mol of CO₂. M = 44 g·mol⁻¹.
3. Which method — and why this one?
m=nM=0.6×44=26.4 g.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 0.6 mol · 44 g·mol⁻¹. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: M = 44 g·mol⁻¹. Circle that word — that is the missing variable.
Find: We are required to find: M = 44 g·mol⁻¹. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: m = nM = 0. Then substitute the given, one line at a time, to get M = 44 g·mol⁻¹.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Mass of 0.6 mol of CO₂. M = 44 g·mol⁻¹.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
m=nM=0.6×44=26.4 g.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
m=nM=0.6×44=26.4 g.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
26.4 g
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
26.4 g
Copy onto your answer sheet — in this order
Answer: 26.4 g
6. Check it like a marker
m=nM=0.6×44=26.4 g.
7. A trap first-timers fall into
52.8 g
2.1 · 6 Marks
The balanced equation for iron burning in oxygen to form Fe₂O₃ is
Notes: The balanced equation for iron burning in oxygen to form Fe₂O₃ is
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: The balanced equation for iron burning in oxygen to form Fe₂O₃ is
In other words — as if you have never seen this before
Oxygen LCM is 6, so 3 O₂ and 2 Fe₂O₃, then 4 Fe.
2. What do we already know?
The balanced equation for iron burning in oxygen to form Fe₂O₃ is
3. Which method — and why this one?
Oxygen LCM is 6, so 3 O₂ and 2 Fe₂O₃, then 4 Fe.
4. Step-by-step working
01 / 07
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 07
Step B — Write the given in a column
The balanced equation for iron burning in oxygen to form Fe₂O₃ is
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
03 / 07
Step C — Name the method in words
Oxygen LCM is 6, so 3 O₂ and 2 Fe₂O₃, then 4 Fe.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
04 / 07
Working
Oxygen LCM is 6, so 3 O₂ and 2 Fe₂O₃, then 4 Fe.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
05 / 07
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
06 / 07
Step F — Box the answer with its unit
4 Fe + 3 O₂ → 2 Fe₂O₃
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
07 / 07
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
4 Fe + 3 O₂ → 2 Fe₂O₃
Copy onto your answer sheet — in this order
Answer: 4 Fe + 3 O₂ → 2 Fe₂O₃
6. Check it like a marker
Oxygen LCM is 6, so 3 O₂ and 2 Fe₂O₃, then 4 Fe.
7. A trap first-timers fall into
Fe + O₂ → Fe₂O₃
2.2 · 6 Marks
Potassium reacts faster with water than sodium because
Notes: Potassium reacts faster with water than sodium because
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Potassium reacts faster with water than sodium because
In other words — as if you have never seen this before
Same group. K has one more shell, so the outer electron is held less tightly.
2. What do we already know?
Potassium reacts faster with water than sodium because
3. Which method — and why this one?
Same group. K has one more shell, so the outer electron is held less tightly.
4. Step-by-step working
01 / 07
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 07
Step B — Write the given in a column
Potassium reacts faster with water than sodium because
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
03 / 07
Step C — Name the method in words
Same group. K has one more shell, so the outer electron is held less tightly.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
04 / 07
Working
Same group. K has one more shell, so the outer electron is held less tightly.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
05 / 07
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
06 / 07
Step F — Box the answer with its unit
the outer electron is further from the nucleus
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
07 / 07
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
the outer electron is further from the nucleus
Copy onto your answer sheet — in this order
Answer: the outer electron is further from the nucleus
6. Check it like a marker
Same group. K has one more shell, so the outer electron is held less tightly.
7. A trap first-timers fall into
potassium has fewer protons
3.1 · 8 Marks · The atom
A neutral chlorine atom has 17 protons. Electrons?
The atom
Formulas
A=Z+N
Mass number = protons + neutrons
Notes: A neutral chlorine atom has 17 protons. Electrons?
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: A neutral chlorine atom has 17 protons. Electrons?
Before any working — hunt first
Given
Numbers and units already in the sentence: 17 protons. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Electrons. Circle that word — that is the missing variable.
Find
We are required to find: Electrons. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: Neutral means electrons equal protons. Then substitute the given, one line at a time, to get Electrons.
In other words — as if you have never seen this before
Neutral means electrons equal protons.
2. What do we already know?
A neutral chlorine atom has 17 protons. Electrons?
3. Which method — and why this one?
Neutral means electrons equal protons.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 17 protons. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Electrons. Circle that word — that is the missing variable.
Find: We are required to find: Electrons. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: Neutral means electrons equal protons. Then substitute the given, one line at a time, to get Electrons.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
A neutral chlorine atom has 17 protons. Electrons?
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
Neutral means electrons equal protons.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
Neutral means electrons equal protons.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
17
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
17
Copy onto your answer sheet — in this order
Answer: 17
6. Check it like a marker
Neutral means electrons equal protons.
7. A trap first-timers fall into
18
7 · 2 Marks · Periodic table
Table salt is a
Formulas
group 1→alkali metalsgroup 7→halogensgroup 8→noble gases
Named groups
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Table salt is a
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Table salt is a. Circle that word — that is the missing variable.
Find
We are required to find: Table salt is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: compound. Then substitute the given, one line at a time, to get Table salt is a.
In other words — as if you have never seen this before
compound
2. What do we already know?
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
compound
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Table salt is a. Circle that word — that is the missing variable.
Find: We are required to find: Table salt is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: compound. Then substitute the given, one line at a time, to get Table salt is a.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
compound
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
NaCl has a fixed formula. Two elements chemically bonded.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
compound
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
compound
Copy onto your answer sheet — in this order
Answer: compound
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
8 · 2 Marks
The bond in NaCl is
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: The bond in NaCl is
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: The bond in NaCl is. Circle that word — that is the missing variable.
Find
We are required to find: The bond in NaCl is. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: ionic. Then substitute the given, one line at a time, to get The bond in NaCl is.
In other words — as if you have never seen this before
ionic
2. What do we already know?
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
ionic
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: The bond in NaCl is. Circle that word — that is the missing variable.
Find: We are required to find: The bond in NaCl is. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: ionic. Then substitute the given, one line at a time, to get The bond in NaCl is.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
ionic
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
A metal and a non-metal. Electrons are transferred.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
ionic
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
ionic
Copy onto your answer sheet — in this order
Answer: ionic
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
9 · 2 Marks · The mole
A balanced chemical equation shows that
The mole
Formulas
n=mM
Amount in moles
n=V22.4(STP, gas in dm³)
Molar volume at STP
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: A balanced chemical equation shows that
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: A balanced chemical equation shows that. Circle that word — that is the missing variable.
Find
We are required to find: A balanced chemical equation shows that. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: atoms are conserved. Then substitute the given, one line at a time, to get A balanced chemical equation shows that.
In other words — as if you have never seen this before
atoms are conserved
2. What do we already know?
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
atoms are conserved
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: A balanced chemical equation shows that. Circle that word — that is the missing variable.
Find: We are required to find: A balanced chemical equation shows that. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: atoms are conserved. Then substitute the given, one line at a time, to get A balanced chemical equation shows that.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
atoms are conserved
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
Count each element on both sides before you stop.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
atoms are conserved
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
atoms are conserved
Copy onto your answer sheet — in this order
Answer: atoms are conserved
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
10 · 2 Marks
A learner in Mahikeng dissolves salt in water until it looks clear. The salt water is a
Notes: A learner in Mahikeng dissolves salt in water until it looks clear. The salt water is a
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: A learner in Mahikeng dissolves salt in water until it looks clear. The salt water is a
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: The salt water is a. Circle that word — that is the missing variable.
Find
We are required to find: The salt water is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: One phase, salt dissolved: a solution is a homogeneous mixture. Then substitute the given, one line at a time, to get The salt water is a.
In other words — as if you have never seen this before
One phase, salt dissolved: a solution is a homogeneous mixture.
2. What do we already know?
A learner in Mahikeng dissolves salt in water until it looks clear. The salt water is a
3. Which method — and why this one?
One phase, salt dissolved: a solution is a homogeneous mixture.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: The salt water is a. Circle that word — that is the missing variable.
Find: We are required to find: The salt water is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: One phase, salt dissolved: a solution is a homogeneous mixture. Then substitute the given, one line at a time, to get The salt water is a.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
A learner in Mahikeng dissolves salt in water until it looks clear. The salt water is a
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
One phase, salt dissolved: a solution is a homogeneous mixture.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
One phase, salt dissolved: a solution is a homogeneous mixture.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
homogeneous mixture
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
homogeneous mixture
Copy onto your answer sheet — in this order
Answer: homogeneous mixture
6. Check it like a marker
One phase, salt dissolved: a solution is a homogeneous mixture.
7. A trap first-timers fall into
compound
11 · 2 Marks
Sodium (2, 8, 1) is in period
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Sodium (2, 8, 1) is in period
Before any working — hunt first
Given
Numbers and units already in the sentence: 2 · 8 · 1. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Sodium (2, 8, 1) is in period. Circle that word — that is the missing variable.
Find
We are required to find: Sodium (2, 8, 1) is in period. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: 3. Then substitute the given, one line at a time, to get Sodium (2, 8, 1) is in period.
In other words — as if you have never seen this before
3
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 2 · 8 · 1. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
3
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 2 · 8 · 1. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Sodium (2, 8, 1) is in period. Circle that word — that is the missing variable.
Find: We are required to find: Sodium (2, 8, 1) is in period. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: 3. Then substitute the given, one line at a time, to get Sodium (2, 8, 1) is in period.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 2 · 8 · 1. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
3
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
The period number equals the number of shells.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
3
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
3
Copy onto your answer sheet — in this order
Answer: 3
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
12 · 2 Marks
M(CO₂) is
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: M(CO₂) is
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: M(CO₂) is. Circle that word — that is the missing variable.
Find
We are required to find: M(CO₂) is. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: 44 g·mol⁻¹. Then substitute the given, one line at a time, to get M(CO₂) is.
In other words — as if you have never seen this before
44 g·mol⁻¹
2. What do we already know?
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
44 g·mol⁻¹
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: M(CO₂) is. Circle that word — that is the missing variable.
Find: We are required to find: M(CO₂) is. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: 44 g·mol⁻¹. Then substitute the given, one line at a time, to get M(CO₂) is.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
44 g·mol⁻¹
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
12 + 16 + 16 = 44. 28 is carbon monoxide.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
44 g·mol⁻¹
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
44 g·mol⁻¹
Copy onto your answer sheet — in this order
Answer: 44 g·mol⁻¹
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
13 · 2 Marks
Electron configuration of Mg (Z = 12)
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Electron configuration of Mg (Z = 12)
Before any working — hunt first
Given
Numbers and units already in the sentence: 12. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Electron configuration of Mg (Z = 12). Circle that word — that is the missing variable.
Find
We are required to find: Electron configuration of Mg (Z = 12). Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: 2, 8, 2. Then substitute the given, one line at a time, to get Electron configuration of Mg (Z = 12).
In other words — as if you have never seen this before
2, 8, 2
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 12. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
2, 8, 2
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 12. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Electron configuration of Mg (Z = 12). Circle that word — that is the missing variable.
Find: We are required to find: Electron configuration of Mg (Z = 12). Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: 2, 8, 2. Then substitute the given, one line at a time, to get Electron configuration of Mg (Z = 12).
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 12. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
2, 8, 2
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
Shells fill 2 then 8. Two electrons remain.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
2, 8, 2
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
2, 8, 2
Copy onto your answer sheet — in this order
Answer: 2, 8, 2
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
14 · 2 Marks
A learner in Johannesburg dissolves salt in water until it looks clear. The salt water is a
Notes: A learner in Johannesburg dissolves salt in water until it looks clear. The salt water is a
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: A learner in Johannesburg dissolves salt in water until it looks clear. The salt water is a
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: The salt water is a. Circle that word — that is the missing variable.
Find
We are required to find: The salt water is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: One phase, salt dissolved: a solution is a homogeneous mixture. Then substitute the given, one line at a time, to get The salt water is a.
In other words — as if you have never seen this before
One phase, salt dissolved: a solution is a homogeneous mixture.
2. What do we already know?
A learner in Johannesburg dissolves salt in water until it looks clear. The salt water is a
3. Which method — and why this one?
One phase, salt dissolved: a solution is a homogeneous mixture.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: The salt water is a. Circle that word — that is the missing variable.
Find: We are required to find: The salt water is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: One phase, salt dissolved: a solution is a homogeneous mixture. Then substitute the given, one line at a time, to get The salt water is a.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
A learner in Johannesburg dissolves salt in water until it looks clear. The salt water is a
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
One phase, salt dissolved: a solution is a homogeneous mixture.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
One phase, salt dissolved: a solution is a homogeneous mixture.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
homogeneous mixture
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
homogeneous mixture
Copy onto your answer sheet — in this order
Answer: homogeneous mixture
6. Check it like a marker
One phase, salt dissolved: a solution is a homogeneous mixture.
7. A trap first-timers fall into
compound
15 · 2 Marks
Sodium-24. Z = 11. Neutrons?
Notes: Sodium-24. Z = 11. Neutrons?
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Sodium-24. Z = 11. Neutrons?
Before any working — hunt first
Given
Numbers and units already in the sentence: 24 · 11. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Neutrons. Circle that word — that is the missing variable.
Find
We are required to find: Neutrons. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: N = A − Z = 24 − 11 = 13. Then substitute the given, one line at a time, to get Neutrons.
In other words — as if you have never seen this before
N=A−Z=24−11=13.
2. What do we already know?
Sodium-24. Z = 11. Neutrons?
3. Which method — and why this one?
N=A−Z=24−11=13.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 24 · 11. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Neutrons. Circle that word — that is the missing variable.
Find: We are required to find: Neutrons. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: N = A − Z = 24 − 11 = 13. Then substitute the given, one line at a time, to get Neutrons.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Sodium-24. Z = 11. Neutrons?
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
N=A−Z=24−11=13.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
N=A−Z=24−11=13.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
13
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
13
Copy onto your answer sheet — in this order
Answer: 13
6. Check it like a marker
N=A−Z=24−11=13.
7. A trap first-timers fall into
11
16 · 2 Marks
n=0.40 mol, M=44 g·mol⁻¹ (CO₂). Mass?
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: n = 0.40 mol, M = 44 g·mol⁻¹ (CO₂). Mass?
Before any working — hunt first
Given
Numbers and units already in the sentence: 0.40 mol · 44 g·mol⁻¹. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Mass. Circle that word — that is the missing variable.
Find
We are required to find: Mass. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: 17. Then substitute the given, one line at a time, to get Mass.
In other words — as if you have never seen this before
17.6 g
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 0.40 mol · 44 g·mol⁻¹. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
17.6 g
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 0.40 mol · 44 g·mol⁻¹. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Mass. Circle that word — that is the missing variable.
Find: We are required to find: Mass. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: 17. Then substitute the given, one line at a time, to get Mass.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 0.40 mol · 44 g·mol⁻¹. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
17.6 g
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
m=n M=0.40×44=17.6 g.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
17.6 g
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
17.6 g
Copy onto your answer sheet — in this order
Answer: 17.6 g
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
17 · 2 Marks
Mass of 0.4 mol of CO₂. M = 44 g·mol⁻¹.
Notes: Mass of 0.4 mol of CO₂. M = 44 g·mol⁻¹.
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Mass of 0.4 mol of CO₂. M = 44 g·mol⁻¹.
Before any working — hunt first
Given
Numbers and units already in the sentence: 0.4 mol · 44 g·mol⁻¹. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: M = 44 g·mol⁻¹. Circle that word — that is the missing variable.
Find
We are required to find: M = 44 g·mol⁻¹. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: m = nM = 0. Then substitute the given, one line at a time, to get M = 44 g·mol⁻¹.
In other words — as if you have never seen this before
m=nM=0.4×44=17.6 g.
2. What do we already know?
Mass of 0.4 mol of CO₂. M = 44 g·mol⁻¹.
3. Which method — and why this one?
m=nM=0.4×44=17.6 g.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 0.4 mol · 44 g·mol⁻¹. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: M = 44 g·mol⁻¹. Circle that word — that is the missing variable.
Find: We are required to find: M = 44 g·mol⁻¹. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: m = nM = 0. Then substitute the given, one line at a time, to get M = 44 g·mol⁻¹.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Mass of 0.4 mol of CO₂. M = 44 g·mol⁻¹.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
m=nM=0.4×44=17.6 g.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
m=nM=0.4×44=17.6 g.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
17.6 g
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
17.6 g
Copy onto your answer sheet — in this order
Answer: 17.6 g
6. Check it like a marker
m=nM=0.4×44=17.6 g.
7. A trap first-timers fall into
35.2 g
18 · 3 Marks
Balanced form of Fe + O₂ → Fe₂O₃ is
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Balanced form of Fe + O₂ → Fe₂O₃ is
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Balanced form of Fe + O₂ → Fe₂O₃ is. Circle that word — that is the missing variable.
Find
We are required to find: Balanced form of Fe + O₂ → Fe₂O₃ is. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: LCM of oxygen is 6: 3 O₂ and 2 Fe₂O₃, then 4 Fe. Then substitute the given, one line at a time, to get Balanced form of Fe + O₂ → Fe₂O₃ is.
In other words — as if you have never seen this before
LCM of oxygen is 6: 3 O₂ and 2 Fe₂O₃, then 4 Fe.
2. What do we already know?
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
LCM of oxygen is 6: 3 O₂ and 2 Fe₂O₃, then 4 Fe.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Balanced form of Fe + O₂ → Fe₂O₃ is. Circle that word — that is the missing variable.
Find: We are required to find: Balanced form of Fe + O₂ → Fe₂O₃ is. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: LCM of oxygen is 6: 3 O₂ and 2 Fe₂O₃, then 4 Fe. Then substitute the given, one line at a time, to get Balanced form of Fe + O₂ → Fe₂O₃ is.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
LCM of oxygen is 6: 3 O₂ and 2 Fe₂O₃, then 4 Fe.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
LCM of oxygen is 6: 3 O₂ and 2 Fe₂O₃, then 4 Fe.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
4 Fe + 3 O₂ → 2 Fe₂O₃
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
4 Fe + 3 O₂ → 2 Fe₂O₃
Copy onto your answer sheet — in this order
Answer: 4 Fe + 3 O₂ → 2 Fe₂O₃
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
19 · 2 Marks
Salt dissolved in water is a
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Salt dissolved in water is a
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Salt dissolved in water is a. Circle that word — that is the missing variable.
Find
We are required to find: Salt dissolved in water is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: homogeneous mixture. Then substitute the given, one line at a time, to get Salt dissolved in water is a.
In other words — as if you have never seen this before
homogeneous mixture
2. What do we already know?
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
homogeneous mixture
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Salt dissolved in water is a. Circle that word — that is the missing variable.
Find: We are required to find: Salt dissolved in water is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: homogeneous mixture. Then substitute the given, one line at a time, to get Salt dissolved in water is a.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
homogeneous mixture
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
One phase. The salt is spread evenly.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
homogeneous mixture
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
homogeneous mixture
Copy onto your answer sheet — in this order
Answer: homogeneous mixture
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
20 · 2 Marks
0.10 mol of solute in 0.50 dm³. c =
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: 0.10 mol of solute in 0.50 dm³. c =
Before any working — hunt first
Given
Numbers and units already in the sentence: 0.10 mol · 0.50 dm³. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: c =. Circle that word — that is the missing variable.
Find
We are required to find: c =. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: 0. Then substitute the given, one line at a time, to get c =.
In other words — as if you have never seen this before
0.20 mol·dm⁻³
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 0.10 mol · 0.50 dm³. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
0.20 mol·dm⁻³
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 0.10 mol · 0.50 dm³. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: c =. Circle that word — that is the missing variable.
Find: We are required to find: c =. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: 0. Then substitute the given, one line at a time, to get c =.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 0.10 mol · 0.50 dm³. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
0.20 mol·dm⁻³
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
c=nV=0.100.50=0.20.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
0.20 mol·dm⁻³
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
0.20 mol·dm⁻³
Copy onto your answer sheet — in this order
Answer: 0.20 mol·dm⁻³
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
21 · 2 Marks
A learner in Mbombela dissolves salt in water until it looks clear. The salt water is a
Notes: A learner in Mbombela dissolves salt in water until it looks clear. The salt water is a
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: A learner in Mbombela dissolves salt in water until it looks clear. The salt water is a
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: The salt water is a. Circle that word — that is the missing variable.
Find
We are required to find: The salt water is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: One phase, salt dissolved: a solution is a homogeneous mixture. Then substitute the given, one line at a time, to get The salt water is a.
In other words — as if you have never seen this before
One phase, salt dissolved: a solution is a homogeneous mixture.
2. What do we already know?
A learner in Mbombela dissolves salt in water until it looks clear. The salt water is a
3. Which method — and why this one?
One phase, salt dissolved: a solution is a homogeneous mixture.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: The salt water is a. Circle that word — that is the missing variable.
Find: We are required to find: The salt water is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: One phase, salt dissolved: a solution is a homogeneous mixture. Then substitute the given, one line at a time, to get The salt water is a.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
A learner in Mbombela dissolves salt in water until it looks clear. The salt water is a
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
One phase, salt dissolved: a solution is a homogeneous mixture.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
One phase, salt dissolved: a solution is a homogeneous mixture.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
homogeneous mixture
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
homogeneous mixture
Copy onto your answer sheet — in this order
Answer: homogeneous mixture
6. Check it like a marker
One phase, salt dissolved: a solution is a homogeneous mixture.
7. A trap first-timers fall into
compound
22 · 2 Marks
0.25 mol of H₂O. M = 18 g·mol⁻¹. Mass?
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: 0.25 mol of H₂O. M = 18 g·mol⁻¹. Mass?
Before any working — hunt first
Given
Numbers and units already in the sentence: 0.25 mol · 18 g·mol⁻¹. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Mass. Circle that word — that is the missing variable.
Find
We are required to find: Mass. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: m = n M = 0. Then substitute the given, one line at a time, to get Mass.
In other words — as if you have never seen this before
m=n M=0.25×18=4.5 g.
2. What do we already know?
Copy these onto the left of your page, one per line, with units: 0.25 mol · 18 g·mol⁻¹. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
m=n M=0.25×18=4.5 g.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 0.25 mol · 18 g·mol⁻¹. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Mass. Circle that word — that is the missing variable.
Find: We are required to find: Mass. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: m = n M = 0. Then substitute the given, one line at a time, to get Mass.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: 0.25 mol · 18 g·mol⁻¹. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
m=n M=0.25×18=4.5 g.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
m=n M=0.25×18=4.5 g.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
4.5 g
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
4.5 g
Copy onto your answer sheet — in this order
Answer: 4.5 g
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
23 · 2 Marks
Sodium-28. Z = 11. Neutrons?
Notes: Sodium-28. Z = 11. Neutrons?
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Sodium-28. Z = 11. Neutrons?
Before any working — hunt first
Given
Numbers and units already in the sentence: 28 · 11. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Neutrons. Circle that word — that is the missing variable.
Find
We are required to find: Neutrons. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: N = A − Z = 28 − 11 = 17. Then substitute the given, one line at a time, to get Neutrons.
In other words — as if you have never seen this before
N=A−Z=28−11=17.
2. What do we already know?
Sodium-28. Z = 11. Neutrons?
3. Which method — and why this one?
N=A−Z=28−11=17.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 28 · 11. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Neutrons. Circle that word — that is the missing variable.
Find: We are required to find: Neutrons. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: N = A − Z = 28 − 11 = 17. Then substitute the given, one line at a time, to get Neutrons.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Sodium-28. Z = 11. Neutrons?
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
N=A−Z=28−11=17.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
N=A−Z=28−11=17.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
17
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
17
Copy onto your answer sheet — in this order
Answer: 17
6. Check it like a marker
N=A−Z=28−11=17.
7. A trap first-timers fall into
11
24 · 2 Marks
Sand mixed with iron filings is a
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Sand mixed with iron filings is a
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Sand mixed with iron filings is a. Circle that word — that is the missing variable.
Find
We are required to find: Sand mixed with iron filings is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: heterogeneous mixture. Then substitute the given, one line at a time, to get Sand mixed with iron filings is a.
In other words — as if you have never seen this before
heterogeneous mixture
2. What do we already know?
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
heterogeneous mixture
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Sand mixed with iron filings is a. Circle that word — that is the missing variable.
Find: We are required to find: Sand mixed with iron filings is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: heterogeneous mixture. Then substitute the given, one line at a time, to get Sand mixed with iron filings is a.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
heterogeneous mixture
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
You can still see two materials.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
heterogeneous mixture
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
heterogeneous mixture
Copy onto your answer sheet — in this order
Answer: heterogeneous mixture
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
25 · 2 Marks
Balance: H₂ + O₂ → H₂O
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Balance: H₂ + O₂ → H₂O
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Balance: H₂ + O₂ → H₂O. Circle that word — that is the missing variable.
Find
We are required to find: Balance: H₂ + O₂ → H₂O. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: 2 H₂ + O₂. Then substitute the given, one line at a time, to get Balance: H₂ + O₂ → H₂O.
In other words — as if you have never seen this before
2 H₂ + O₂ → 2 H₂O
2. What do we already know?
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
2 H₂ + O₂ → 2 H₂O
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Balance: H₂ + O₂ → H₂O. Circle that word — that is the missing variable.
Find: We are required to find: Balance: H₂ + O₂ → H₂O. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: 2 H₂ + O₂. Then substitute the given, one line at a time, to get Balance: H₂ + O₂ → H₂O.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
2 H₂ + O₂ → 2 H₂O
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Reason
Four H atoms and two O atoms on each side.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
2 H₂ + O₂ → 2 H₂O
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
2 H₂ + O₂ → 2 H₂O
Copy onto your answer sheet — in this order
Answer: 2 H₂ + O₂ → 2 H₂O
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
26 · 2 Marks
A learner in a national paper dissolves salt in water until it looks clear. The salt water is a
Notes: A learner in a national paper dissolves salt in water until it looks clear. The salt water is a
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: A learner in a national paper dissolves salt in water until it looks clear. The salt water is a
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: The salt water is a. Circle that word — that is the missing variable.
Find
We are required to find: The salt water is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: One phase, salt dissolved: a solution is a homogeneous mixture. Then substitute the given, one line at a time, to get The salt water is a.
In other words — as if you have never seen this before
One phase, salt dissolved: a solution is a homogeneous mixture.
2. What do we already know?
A learner in a national paper dissolves salt in water until it looks clear. The salt water is a
3. Which method — and why this one?
One phase, salt dissolved: a solution is a homogeneous mixture.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: The salt water is a. Circle that word — that is the missing variable.
Find: We are required to find: The salt water is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: One phase, salt dissolved: a solution is a homogeneous mixture. Then substitute the given, one line at a time, to get The salt water is a.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
A learner in a national paper dissolves salt in water until it looks clear. The salt water is a
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
One phase, salt dissolved: a solution is a homogeneous mixture.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
One phase, salt dissolved: a solution is a homogeneous mixture.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
homogeneous mixture
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
homogeneous mixture
Copy onto your answer sheet — in this order
Answer: homogeneous mixture
6. Check it like a marker
One phase, salt dissolved: a solution is a homogeneous mixture.
7. A trap first-timers fall into
compound
27 · 2 Marks
Sodium-23. Z = 11. Neutrons?
Notes: Sodium-23. Z = 11. Neutrons?
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Sodium-23. Z = 11. Neutrons?
Before any working — hunt first
Given
Numbers and units already in the sentence: 23 · 11. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: Neutrons. Circle that word — that is the missing variable.
Find
We are required to find: Neutrons. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: N = A − Z = 23 − 11 = 12. Then substitute the given, one line at a time, to get Neutrons.
In other words — as if you have never seen this before
N=A−Z=23−11=12.
2. What do we already know?
Sodium-23. Z = 11. Neutrons?
3. Which method — and why this one?
N=A−Z=23−11=12.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 23 · 11. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Neutrons. Circle that word — that is the missing variable.
Find: We are required to find: Neutrons. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: N = A − Z = 23 − 11 = 12. Then substitute the given, one line at a time, to get Neutrons.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Sodium-23. Z = 11. Neutrons?
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
N=A−Z=23−11=12.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
N=A−Z=23−11=12.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
12
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
12
Copy onto your answer sheet — in this order
Answer: 12
6. Check it like a marker
N=A−Z=23−11=12.
7. A trap first-timers fall into
11
28 · 2 Marks
Raising the temperature of a gas increases the
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Raising the temperature of a gas increases the
In other words — as if you have never seen this before
average kinetic energy
2. What do we already know?
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
3. Which method — and why this one?
average kinetic energy
4. Step-by-step working
01 / 07
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 07
Step B — Write the given in a column
Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
03 / 07
Step C — Name the method in words
average kinetic energy
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
04 / 07
Reason
Temperature is a measure of average kinetic energy.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
05 / 07
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
06 / 07
Step F — Box the answer with its unit
average kinetic energy of the particles
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
07 / 07
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
average kinetic energy of the particles
Copy onto your answer sheet — in this order
Answer: average kinetic energy of the particles
6. Check it like a marker
Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?
7. A trap first-timers fall into
First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”
29 · 2 Marks
Mass of 0.7 mol of CO₂. M = 44 g·mol⁻¹.
Notes: Mass of 0.7 mol of CO₂. M = 44 g·mol⁻¹.
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Mass of 0.7 mol of CO₂. M = 44 g·mol⁻¹.
Before any working — hunt first
Given
Numbers and units already in the sentence: 0.7 mol · 44 g·mol⁻¹. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: M = 44 g·mol⁻¹. Circle that word — that is the missing variable.
Find
We are required to find: M = 44 g·mol⁻¹. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: m = nM = 0. Then substitute the given, one line at a time, to get M = 44 g·mol⁻¹.
In other words — as if you have never seen this before
m=nM=0.7×44=30.8 g.
2. What do we already know?
Mass of 0.7 mol of CO₂. M = 44 g·mol⁻¹.
3. Which method — and why this one?
m=nM=0.7×44=30.8 g.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: 0.7 mol · 44 g·mol⁻¹. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: M = 44 g·mol⁻¹. Circle that word — that is the missing variable.
Find: We are required to find: M = 44 g·mol⁻¹. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: m = nM = 0. Then substitute the given, one line at a time, to get M = 44 g·mol⁻¹.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
Mass of 0.7 mol of CO₂. M = 44 g·mol⁻¹.
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
m=nM=0.7×44=30.8 g.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
m=nM=0.7×44=30.8 g.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
30.8 g
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
30.8 g
Copy onto your answer sheet — in this order
Answer: 30.8 g
6. Check it like a marker
m=nM=0.7×44=30.8 g.
7. A trap first-timers fall into
61.6 g
30 · 2 Marks
A learner in Gqeberha dissolves salt in water until it looks clear. The salt water is a
Notes: A learner in Gqeberha dissolves salt in water until it looks clear. The salt water is a
How we got there
Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.
Explain in another language · 11
1. What is the question asking?
Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: A learner in Gqeberha dissolves salt in water until it looks clear. The salt water is a
Before any working — hunt first
Given
Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing
After you copy the given, the letter that still has no number is missing. The paper is pointing at: The salt water is a. Circle that word — that is the missing variable.
Find
We are required to find: The salt water is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate
What we need to calculate: One phase, salt dissolved: a solution is a homogeneous mixture. Then substitute the given, one line at a time, to get The salt water is a.
In other words — as if you have never seen this before
One phase, salt dissolved: a solution is a homogeneous mixture.
2. What do we already know?
A learner in Gqeberha dissolves salt in water until it looks clear. The salt water is a
3. Which method — and why this one?
One phase, salt dissolved: a solution is a homogeneous mixture.
4. Step-by-step working
01 / 08
Step A — Read the question twice
Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
02 / 08
Step A2 — Hunt: Given, Missing, Find, Calculate
Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.
Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: The salt water is a. Circle that word — that is the missing variable.
Find: We are required to find: The salt water is a. Write that as a symbol on the left, with a question mark, before you touch a formula.
Calculate: What we need to calculate: One phase, salt dissolved: a solution is a homogeneous mixture. Then substitute the given, one line at a time, to get The salt water is a.
Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).
03 / 08
Step B — Write the given in a column
A learner in Gqeberha dissolves salt in water until it looks clear. The salt water is a
Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.
04 / 08
Step C — Name the method in words
One phase, salt dissolved: a solution is a homogeneous mixture.
Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.
05 / 08
Working
One phase, salt dissolved: a solution is a homogeneous mixture.
Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.
06 / 08
Step G — Sense-check the size
Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.
Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.
07 / 08
Step F — Box the answer with its unit
homogeneous mixture
Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.
08 / 08
Step H — What the marker is looking for
On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.
Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.
5. The answer
homogeneous mixture
Copy onto your answer sheet — in this order
Answer: homogeneous mixture
6. Check it like a marker
One phase, salt dissolved: a solution is a homogeneous mixture.