Exercise 1 — IGCSE 0653 Mar 2023 Paper 32 Q2
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(change) chemical AND
Cambridge IGCSE·Combined Sciences 0653·Chemistry
Acids Bases Salts
Key knowledge — Acids Bases Salts
Formulas & equations
acid + metal → salt + hydrogenacid + metal oxide → salt + wateracid + metal hydroxide → salt + water (neutralisation)acid + metal carbonate → salt + water + carbon dioxide
Key facts & rules
- Acid: produces H⁺ ions in solution. pH < 7.
- Alkali: produces OH⁻ ions in solution. pH > 7. (Bases that dissolve in water.)
- Neutralisation: H⁺ + OH⁻ → H₂O.
- pH scale: 0–14. pH 7 = neutral. Strong acids have lower pH than weak acids at same concentration.
- Strong acid: fully dissociates (HCl, H₂SO₄, HNO₃). Weak acid: partially dissociates (CH₃COOH).
- Making insoluble salts: mix two solutions containing the required ions → filter the precipitate.
- Making soluble salts: add excess solid acid/metal/metal carbonate to acid → filter → evaporate.
- Titration: used to find exact volume of acid/alkali needed for neutralisation.
IGCSE Chemistry — Acids, Bases & Salts
136 Cambridge IGCSE 0653 Combined Sciences past paper questions on acids, bases & salts, across Theory, Multiple Choice and Alternative to Practical.
About Acids, Bases & Salts on IGCSE 0653
Acids produce hydrogen ions in solution; bases neutralise acids. Salt preparation methods include neutralisation, reaction with a metal, and reaction with a metal oxide or carbonate. The pH scale measures acidity and alkalinity.
What's covered:
- pH scale and indicators
- Reactions of acids with metals, metal oxides, carbonates
- Neutralisation and salt formation
- Making salts: titration, excess solid method
- Strong and weak acids
- Oxides: acidic, basic, amphoteric, neutral
Theory
Acids, Bases & Salts — Core11 · Paper 3
Exercise 2 — IGCSE 0653 Mar 2024 Paper 32 Q5
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(grey shading) nitrogen
Exercise 3 — IGCSE 0653 May/Jun 2023 Paper 32 Q2
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(concentrated) high ratio of, solute / sodium chloride / ions, to solvent / water OR large (relative) amount of, solute / sodium
Exercise 4 — IGCSE 0653 May/Jun 2023 Paper 32 Q5
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(physical property) high density / high melting point / electrical conductor / heat or thermal conductor
Exercise 5 — IGCSE 0653 May/Jun 2023 Paper 33 Q5
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magnesium oxide + sulfuric acid magnesium sulfate + water ;
Exercise 6 — IGCSE 0653 May/Jun 2023 Paper 31 Q8
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sulfuric (acid) AND water
Exercise 7 — IGCSE 0653 May/Jun 2024 Paper 33 Q2
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oxygen
Exercise 8 — IGCSE 0653 May/Jun 2024 Paper 31 Q8
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time
Exercise 9 — IGCSE 0653 May/Jun 2025 Paper 33 Q5
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(add UI to the acid and) look at the colour / state acid gives red colour
Exercise 10 — IGCSE 0653 Oct/Nov 2023 Paper 31 Q2
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test (anhydrous) copper sulfate
Exercise 11 — IGCSE 0653 Oct/Nov 2023 Paper 31 Q8
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(2,) 8, 7
Acids, Bases & Salts — Extended5 · Paper 4
Exercise 1 — IGCSE 0653 Mar 2023 Paper 42 Q5
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solute: (solid) magnesium sulfate
Exercise 2 — IGCSE 0653 May/Jun 2024 Paper 43 Q5
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zinc sulfate
Exercise 3 — IGCSE 0653 May/Jun 2024 Paper 42 Q8
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hydrogen / H
Exercise 4 — IGCSE 0653 Oct/Nov 2023 Paper 42 Q2
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hydrochloric (acid)
Exercise 5 — IGCSE 0653 Oct/Nov 2023 Paper 42 Q5
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magnesium AND
Multiple choice
Acids, Bases & Salts — Core MCQ49 · Paper 1
Question 1 — IGCSE 0653 Mar 2023 Paper 12 Q18
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Correct answer: C
Question 2 — IGCSE 0653 Mar 2023 Paper 12 Q19
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Correct answer: B
Question 3 — IGCSE 0653 Mar 2023 Paper 12 Q20
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Correct answer: D
Question 4 — IGCSE 0653 Mar 2024 Paper 12 Q20
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Correct answer: A
Question 5 — IGCSE 0653 Mar 2024 Paper 12 Q21
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Correct answer: A
Question 6 — IGCSE 0653 Mar 2024 Paper 12 Q22
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Correct answer: B
Question 7 — IGCSE 0653 Mar 2025 Paper 12 Q26
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Correct answer: C
Question 8 — IGCSE 0653 Mar 2025 Paper 12 Q27
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Correct answer: C
Question 9 — IGCSE 0653 Mar 2025 Paper 12 Q28
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Correct answer: B
Question 10 — IGCSE 0653 May/Jun 2023 Paper 13 Q20
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Correct answer: B
Question 11 — IGCSE 0653 May/Jun 2023 Paper 13 Q21
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Correct answer: B
Question 12 — IGCSE 0653 May/Jun 2023 Paper 12 Q22
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Correct answer: C
Question 13 — IGCSE 0653 May/Jun 2023 Paper 13 Q22
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Correct answer: C
Question 14 — IGCSE 0653 May/Jun 2023 Paper 12 Q23
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Correct answer: C
Question 15 — IGCSE 0653 May/Jun 2023 Paper 13 Q23
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Correct answer: C
Question 16 — IGCSE 0653 May/Jun 2023 Paper 12 Q24
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Correct answer: C
Question 17 — IGCSE 0653 May/Jun 2023 Paper 12 Q25
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Correct answer: C
Question 18 — IGCSE 0653 May/Jun 2023 Paper 12 Q26
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Correct answer: A
Question 19 — IGCSE 0653 May/Jun 2023 Paper 12 Q27
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Correct answer: B
Question 20 — IGCSE 0653 May/Jun 2023 Paper 12 Q28
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Correct answer: A
Question 21 — IGCSE 0653 May/Jun 2024 Paper 12 Q14
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Correct answer: D
Question 22 — IGCSE 0653 May/Jun 2024 Paper 12 Q15
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Correct answer: B
Question 23 — IGCSE 0653 May/Jun 2024 Paper 12 Q16
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Correct answer: D
Question 24 — IGCSE 0653 May/Jun 2024 Paper 12 Q22
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Correct answer: A
Question 25 — IGCSE 0653 May/Jun 2024 Paper 13 Q22
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Correct answer: D
Question 26 — IGCSE 0653 May/Jun 2024 Paper 12 Q23
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Correct answer: D
Question 27 — IGCSE 0653 May/Jun 2024 Paper 13 Q23
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Correct answer: C
Question 28 — IGCSE 0653 May/Jun 2024 Paper 12 Q24
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Correct answer: A
Question 29 — IGCSE 0653 May/Jun 2024 Paper 13 Q24
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Correct answer: B
Question 30 — IGCSE 0653 May/Jun 2024 Paper 13 Q25
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Correct answer: D
Question 31 — IGCSE 0653 May/Jun 2024 Paper 13 Q26
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Correct answer: A
Question 32 — IGCSE 0653 May/Jun 2024 Paper 13 Q27
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Correct answer: B
Question 33 — IGCSE 0653 May/Jun 2024 Paper 13 Q28
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Correct answer: B
Question 34 — IGCSE 0653 May/Jun 2025 Paper 11 Q20
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Correct answer: C
Question 35 — IGCSE 0653 May/Jun 2025 Paper 13 Q20
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Correct answer: D
Question 36 — IGCSE 0653 May/Jun 2025 Paper 11 Q21
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Correct answer: B
Question 37 — IGCSE 0653 May/Jun 2025 Paper 13 Q21
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Correct answer: B
Question 38 — IGCSE 0653 May/Jun 2025 Paper 11 Q22
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Correct answer: C
Question 39 — IGCSE 0653 May/Jun 2025 Paper 13 Q22
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Correct answer: A
Question 40 — IGCSE 0653 May/Jun 2025 Paper 13 Q23
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Correct answer: D
Question 41 — IGCSE 0653 May/Jun 2025 Paper 11 Q27
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Correct answer: B
Question 42 — IGCSE 0653 May/Jun 2025 Paper 11 Q28
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Correct answer: B
Question 43 — IGCSE 0653 May/Jun 2025 Paper 11 Q29
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Correct answer: C
Question 44 — IGCSE 0653 Oct/Nov 2023 Paper 11 Q20
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Correct answer: D
Question 45 — IGCSE 0653 Oct/Nov 2023 Paper 12 Q20
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Correct answer: A
Question 46 — IGCSE 0653 Oct/Nov 2023 Paper 13 Q20
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Correct answer: A
Question 47 — IGCSE 0653 Oct/Nov 2023 Paper 11 Q21
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Correct answer: A
Question 48 — IGCSE 0653 Oct/Nov 2023 Paper 12 Q21
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Correct answer: C
Question 49 — IGCSE 0653 Oct/Nov 2023 Paper 13 Q21
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Correct answer: C
Acids, Bases & Salts — Extended MCQ34 · Paper 2
Question 1 — IGCSE 0653 Mar 2025 Paper 22 Q14
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Correct answer: D
Question 2 — IGCSE 0653 Mar 2025 Paper 22 Q15
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Correct answer: C
Question 3 — IGCSE 0653 Mar 2025 Paper 22 Q16
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Correct answer: D
Question 4 — IGCSE 0653 Mar 2025 Paper 22 Q17
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Correct answer: A
Question 5 — IGCSE 0653 Mar 2025 Paper 22 Q23
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Correct answer: B
Question 6 — IGCSE 0653 Mar 2025 Paper 22 Q24
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Correct answer: A
Question 7 — IGCSE 0653 May/Jun 2023 Paper 23 Q20
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Correct answer: D
Question 8 — IGCSE 0653 May/Jun 2023 Paper 22 Q21
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Correct answer: B
Question 9 — IGCSE 0653 May/Jun 2023 Paper 23 Q21
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Correct answer: C
Question 10 — IGCSE 0653 May/Jun 2023 Paper 21 Q22
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Correct answer: D
Question 11 — IGCSE 0653 May/Jun 2023 Paper 22 Q22
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Correct answer: C
Question 12 — IGCSE 0653 May/Jun 2023 Paper 23 Q22
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Correct answer: C
Question 13 — IGCSE 0653 May/Jun 2023 Paper 21 Q23
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Correct answer: B
Question 14 — IGCSE 0653 May/Jun 2023 Paper 22 Q23
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Correct answer: A
Question 15 — IGCSE 0653 May/Jun 2023 Paper 23 Q23
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Correct answer: C
Question 16 — IGCSE 0653 May/Jun 2024 Paper 21 Q22
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Correct answer: B
Question 17 — IGCSE 0653 May/Jun 2024 Paper 21 Q23
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Correct answer: B
Question 18 — IGCSE 0653 May/Jun 2024 Paper 23 Q23
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Correct answer: A
Question 19 — IGCSE 0653 May/Jun 2024 Paper 21 Q24
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Correct answer: A
Question 20 — IGCSE 0653 May/Jun 2024 Paper 23 Q24
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Correct answer: B
Question 21 — IGCSE 0653 May/Jun 2024 Paper 23 Q25
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Correct answer: D
Question 22 — IGCSE 0653 May/Jun 2024 Paper 23 Q26
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Correct answer: B
Question 23 — IGCSE 0653 May/Jun 2024 Paper 23 Q27
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Correct answer: D
Question 24 — IGCSE 0653 Oct/Nov 2023 Paper 22 Q19
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Correct answer: A
Question 25 — IGCSE 0653 Oct/Nov 2023 Paper 23 Q19
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Correct answer: C
Question 26 — IGCSE 0653 Oct/Nov 2023 Paper 22 Q20
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Correct answer: A
Question 27 — IGCSE 0653 Oct/Nov 2023 Paper 23 Q20
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Correct answer: D
Question 28 — IGCSE 0653 Oct/Nov 2023 Paper 22 Q21
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Correct answer: C
Question 29 — IGCSE 0653 Oct/Nov 2023 Paper 23 Q21
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Correct answer: C
Question 30 — IGCSE 0653 Oct/Nov 2023 Paper 21 Q22
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Correct answer: A
Question 31 — IGCSE 0653 Oct/Nov 2023 Paper 22 Q22
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Correct answer: C
Question 32 — IGCSE 0653 Oct/Nov 2023 Paper 21 Q23
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Correct answer: C
Question 33 — IGCSE 0653 Oct/Nov 2023 Paper 22 Q23
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Correct answer: C
Question 34 — IGCSE 0653 Oct/Nov 2023 Paper 21 Q24
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Correct answer: C
Alternative to practical
Acids, Bases & Salts — ATP37 questions
Exercise 1 — IGCSE 0653 Mar 2023 Paper 52 Q1
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temperature recorded
Exercise 2 — IGCSE 0653 Mar 2023 Paper 62 Q1
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all results recorded
Exercise 3 — IGCSE 0653 Mar 2023 Paper 52 Q2
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temperature for ‘no acid added’ quoted
Exercise 4 — IGCSE 0653 Mar 2023 Paper 62 Q2
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21.0
Exercise 5 — IGCSE 0653 Mar 2023 Paper 52 Q4
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One mark from each section and any two other marking points:
Exercise 6 — IGCSE 0653 Mar 2024 Paper 52 Q3
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temperature of H measured to nearest 0.5 °C
Exercise 7 — IGCSE 0653 Mar 2024 Paper 62 Q3
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24.0 (°C)
Exercise 8 — IGCSE 0653 Mar 2024 Paper 52 Q4
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first I value recorded to at least 2 decimal places
Exercise 9 — IGCSE 0653 Mar 2025 Paper 52 Q1
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all 10 values recorded in order of height
Exercise 10 — IGCSE 0653 Mar 2025 Paper 62 Q1
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all five lengths correct
Exercise 11 — IGCSE 0653 Mar 2025 Paper 52 Q2
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white precipitate
Exercise 12 — IGCSE 0653 Mar 2025 Paper 62 Q2
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row or column showing correct mixture
Exercise 13 — IGCSE 0653 Mar 2025 Paper 52 Q4
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w and h recorded and w > h
Exercise 14 — IGCSE 0653 Mar 2025 Paper 62 Q4
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h = 1.4 (cm)
Exercise 15 — IGCSE 0653 May/Jun 2023 Paper 63 Q1
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size – more than half available vertical space
Exercise 16 — IGCSE 0653 May/Jun 2023 Paper 63 Q2
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soak a splint into the solution and hold in a blue flame / spray solution into a blue flame / evaporate solution to form crystals
Exercise 17 — IGCSE 0653 May/Jun 2023 Paper 52 Q3
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both values to same and at least 1 decimal place
Exercise 18 — IGCSE 0653 May/Jun 2023 Paper 62 Q3
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touching hot test-tube may cause injury / AW
Exercise 19 — IGCSE 0653 May/Jun 2023 Paper 51 Q4
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V in range 2.0 to 3.5 (V)
Exercise 20 — IGCSE 0653 May/Jun 2023 Paper 52 Q4
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values shown for u and v in first row that add up to 95.0 cm
Exercise 21 — IGCSE 0653 May/Jun 2024 Paper 51 Q2
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result for 1 spatula recorded
Exercise 22 — IGCSE 0653 May/Jun 2024 Paper 52 Q2
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test 1 – (light) blue ppt.
Exercise 23 — IGCSE 0653 May/Jun 2024 Paper 61 Q2
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21
Exercise 24 — IGCSE 0653 May/Jun 2024 Paper 62 Q2
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mixture of colours seen (blue-green and yellow) / (green-blue) colour only appears for a short time
Exercise 25 — IGCSE 0653 May/Jun 2024 Paper 63 Q3
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pencil is insoluble / ink is soluble
Exercise 26 — IGCSE 0653 May/Jun 2024 Paper 51 Q4
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One mark from each section and any two other marking points:
Exercise 27 — IGCSE 0653 May/Jun 2024 Paper 52 Q4
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full set of results for column
Exercise 28 — IGCSE 0653 May/Jun 2025 Paper 63 Q1
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number of ungerminated seeds recorded as 18
Exercise 29 — IGCSE 0653 May/Jun 2025 Paper 63 Q2
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ammonia / a gas is formed and turns (damp red) litmus paper blue
Exercise 30 — IGCSE 0653 May/Jun 2025 Paper 51 Q4
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answer in range 13.0 - 17.0 (cm)
Exercise 31 — IGCSE 0653 May/Jun 2025 Paper 52 Q4
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One marking point from each section and any two others (if one section is missing max 6 etc.):
Exercise 32 — IGCSE 0653 May/Jun 2025 Paper 61 Q4
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1.5 (cm)
Exercise 33 — IGCSE 0653 May/Jun 2025 Paper 62 Q4
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One marking point from each section and any two others (if one section is missing max 6 etc.):
Exercise 34 — IGCSE 0653 May/Jun 2025 Paper 63 Q4
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6.5
Exercise 35 — IGCSE 0653 Oct/Nov 2023 Paper 62 Q2
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1.2 (g)
Exercise 36 — IGCSE 0653 Oct/Nov 2023 Paper 62 Q3
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one mark from each section and any two other marking points
Exercise 37 — IGCSE 0653 Oct/Nov 2023 Paper 51 Q4
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one mark from each section and any two other marking points
All Acids, Bases & Salts questions in this collection
| Type | Level | Paper | Session | Q# | Marks | Answer / key |
|---|---|---|---|---|---|---|
| ATP | Core | Paper 52 | Mar 2023 | Q1 | 13 marks | temperature recorded |
| ATP | Core | Paper 52 | Mar 2023 | Q2 | 13 marks | temperature for ‘no acid added’ quoted |
| ATP | Core | Paper 52 | Mar 2023 | Q4 | 7 marks | One mark from each section and any two other marking points: |
| ATP | Core | Paper 52 | Mar 2024 | Q3 | 13 marks | temperature of H measured to nearest 0.5 °C |
| ATP | Core | Paper 52 | Mar 2024 | Q4 | 13 marks | first I value recorded to at least 2 decimal places |
| ATP | Core | Paper 52 | Mar 2025 | Q1 | 13 marks | all 10 values recorded in order of height |
| ATP | Core | Paper 52 | Mar 2025 | Q2 | 7 marks | white precipitate |
| ATP | Core | Paper 52 | Mar 2025 | Q4 | 13 marks | w and h recorded and w > h |
| ATP | Core | Paper 52 | May/Jun 2023 | Q3 | 13 marks | both values to same and at least 1 decimal place |
| ATP | Core | Paper 51 | May/Jun 2023 | Q4 | 13 marks | V in range 2.0 to 3.5 (V) |
| ATP | Core | Paper 52 | May/Jun 2023 | Q4 | 13 marks | values shown for u and v in first row that add up to 95.0 cm |
| ATP | Core | Paper 51 | May/Jun 2024 | Q2 | 13 marks | result for 1 spatula recorded |
| ATP | Core | Paper 52 | May/Jun 2024 | Q2 | 7 marks | test 1 – (light) blue ppt. |
| ATP | Core | Paper 51 | May/Jun 2024 | Q4 | 7 marks | One mark from each section and any two other marking points: |
| ATP | Core | Paper 52 | May/Jun 2024 | Q4 | 13 marks | full set of results for column |
| ATP | Core | Paper 51 | May/Jun 2025 | Q4 | 13 marks | answer in range 13.0 - 17.0 (cm) |
| ATP | Core | Paper 52 | May/Jun 2025 | Q4 | 7 marks | One marking point from each section and any two others (if one section is missin… |
| ATP | Core | Paper 51 | Oct/Nov 2023 | Q4 | 7 marks | one mark from each section and any two other marking points |
| ATP | Extended | Paper 62 | Mar 2023 | Q1 | 13 marks | all results recorded |
| ATP | Extended | Paper 62 | Mar 2023 | Q2 | 13 marks | 21.0 |
| ATP | Extended | Paper 62 | Mar 2024 | Q3 | 13 marks | 24.0 (°C) |
| ATP | Extended | Paper 62 | Mar 2025 | Q1 | 13 marks | all five lengths correct |
| ATP | Extended | Paper 62 | Mar 2025 | Q2 | 7 marks | row or column showing correct mixture |
| ATP | Extended | Paper 62 | Mar 2025 | Q4 | 13 marks | h = 1.4 (cm) |
| ATP | Extended | Paper 63 | May/Jun 2023 | Q1 | 13 marks | size – more than half available vertical space |
| ATP | Extended | Paper 63 | May/Jun 2023 | Q2 | 13 marks | soak a splint into the solution and hold in a blue flame / spray solution into a… |
| ATP | Extended | Paper 62 | May/Jun 2023 | Q3 | 13 marks | touching hot test-tube may cause injury / AW |
| ATP | Extended | Paper 61 | May/Jun 2024 | Q2 | 13 marks | 21 |
| ATP | Extended | Paper 62 | May/Jun 2024 | Q2 | 7 marks | mixture of colours seen (blue-green and yellow) / (green-blue) colour only appea… |
| ATP | Extended | Paper 63 | May/Jun 2024 | Q3 | 13 marks | pencil is insoluble / ink is soluble |
| ATP | Extended | Paper 63 | May/Jun 2025 | Q1 | 13 marks | number of ungerminated seeds recorded as 18 |
| ATP | Extended | Paper 63 | May/Jun 2025 | Q2 | 7 marks | ammonia / a gas is formed and turns (damp red) litmus paper blue |
| ATP | Extended | Paper 61 | May/Jun 2025 | Q4 | 13 marks | 1.5 (cm) |
| ATP | Extended | Paper 62 | May/Jun 2025 | Q4 | 7 marks | One marking point from each section and any two others (if one section is missin… |
| ATP | Extended | Paper 63 | May/Jun 2025 | Q4 | 13 marks | 6.5 |
| ATP | Extended | Paper 62 | Oct/Nov 2023 | Q2 | 7 marks | 1.2 (g) |
| ATP | Extended | Paper 62 | Oct/Nov 2023 | Q3 | 7 marks | one mark from each section and any two other marking points |
| MCQ | Core | Paper 12 | Mar 2023 | Q18 | 1 mark | C |
| MCQ | Core | Paper 12 | Mar 2023 | Q19 | 1 mark | B |
| MCQ | Core | Paper 12 | Mar 2023 | Q20 | 1 mark | D |
| MCQ | Core | Paper 12 | Mar 2024 | Q20 | 1 mark | A |
| MCQ | Core | Paper 12 | Mar 2024 | Q21 | 1 mark | A |
| MCQ | Core | Paper 12 | Mar 2024 | Q22 | 1 mark | B |
| MCQ | Core | Paper 12 | Mar 2025 | Q26 | 1 mark | C |
| MCQ | Core | Paper 12 | Mar 2025 | Q27 | 1 mark | C |
| MCQ | Core | Paper 12 | Mar 2025 | Q28 | 1 mark | B |
| MCQ | Core | Paper 13 | May/Jun 2023 | Q20 | 1 mark | B |
| MCQ | Core | Paper 13 | May/Jun 2023 | Q21 | 1 mark | B |
| MCQ | Core | Paper 12 | May/Jun 2023 | Q22 | 1 mark | C |
| MCQ | Core | Paper 13 | May/Jun 2023 | Q22 | 1 mark | C |
| MCQ | Core | Paper 12 | May/Jun 2023 | Q23 | 1 mark | C |
| MCQ | Core | Paper 13 | May/Jun 2023 | Q23 | 1 mark | C |
| MCQ | Core | Paper 12 | May/Jun 2023 | Q24 | 1 mark | C |
| MCQ | Core | Paper 12 | May/Jun 2023 | Q25 | 1 mark | C |
| MCQ | Core | Paper 12 | May/Jun 2023 | Q26 | 1 mark | A |
| MCQ | Core | Paper 12 | May/Jun 2023 | Q27 | 1 mark | B |
| MCQ | Core | Paper 12 | May/Jun 2023 | Q28 | 1 mark | A |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q14 | 1 mark | D |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q15 | 1 mark | B |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q16 | 1 mark | D |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q22 | 1 mark | A |
| MCQ | Core | Paper 13 | May/Jun 2024 | Q22 | 1 mark | D |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q23 | 1 mark | D |
| MCQ | Core | Paper 13 | May/Jun 2024 | Q23 | 1 mark | C |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q24 | 1 mark | A |
| MCQ | Core | Paper 13 | May/Jun 2024 | Q24 | 1 mark | B |
| MCQ | Core | Paper 13 | May/Jun 2024 | Q25 | 1 mark | D |
| MCQ | Core | Paper 13 | May/Jun 2024 | Q26 | 1 mark | A |
| MCQ | Core | Paper 13 | May/Jun 2024 | Q27 | 1 mark | B |
| MCQ | Core | Paper 13 | May/Jun 2024 | Q28 | 1 mark | B |
| MCQ | Core | Paper 11 | May/Jun 2025 | Q20 | 1 mark | C |
| MCQ | Core | Paper 13 | May/Jun 2025 | Q20 | 1 mark | D |
| MCQ | Core | Paper 11 | May/Jun 2025 | Q21 | 1 mark | B |
| MCQ | Core | Paper 13 | May/Jun 2025 | Q21 | 1 mark | B |
| MCQ | Core | Paper 11 | May/Jun 2025 | Q22 | 1 mark | C |
| MCQ | Core | Paper 13 | May/Jun 2025 | Q22 | 1 mark | A |
| MCQ | Core | Paper 13 | May/Jun 2025 | Q23 | 1 mark | D |
| MCQ | Core | Paper 11 | May/Jun 2025 | Q27 | 1 mark | B |
| MCQ | Core | Paper 11 | May/Jun 2025 | Q28 | 1 mark | B |
| MCQ | Core | Paper 11 | May/Jun 2025 | Q29 | 1 mark | C |
| MCQ | Core | Paper 11 | Oct/Nov 2023 | Q20 | 1 mark | D |
| MCQ | Core | Paper 12 | Oct/Nov 2023 | Q20 | 1 mark | A |
| MCQ | Core | Paper 13 | Oct/Nov 2023 | Q20 | 1 mark | A |
| MCQ | Core | Paper 11 | Oct/Nov 2023 | Q21 | 1 mark | A |
| MCQ | Core | Paper 12 | Oct/Nov 2023 | Q21 | 1 mark | C |
| MCQ | Core | Paper 13 | Oct/Nov 2023 | Q21 | 1 mark | C |
| MCQ | Extended | Paper 22 | Mar 2025 | Q14 | 1 mark | D |
| MCQ | Extended | Paper 22 | Mar 2025 | Q15 | 1 mark | C |
| MCQ | Extended | Paper 22 | Mar 2025 | Q16 | 1 mark | D |
| MCQ | Extended | Paper 22 | Mar 2025 | Q17 | 1 mark | A |
| MCQ | Extended | Paper 22 | Mar 2025 | Q23 | 1 mark | B |
| MCQ | Extended | Paper 22 | Mar 2025 | Q24 | 1 mark | A |
| MCQ | Extended | Paper 23 | May/Jun 2023 | Q20 | 1 mark | D |
| MCQ | Extended | Paper 22 | May/Jun 2023 | Q21 | 1 mark | B |
| MCQ | Extended | Paper 23 | May/Jun 2023 | Q21 | 1 mark | C |
| MCQ | Extended | Paper 21 | May/Jun 2023 | Q22 | 1 mark | D |
| MCQ | Extended | Paper 22 | May/Jun 2023 | Q22 | 1 mark | C |
| MCQ | Extended | Paper 23 | May/Jun 2023 | Q22 | 1 mark | C |
| MCQ | Extended | Paper 21 | May/Jun 2023 | Q23 | 1 mark | B |
| MCQ | Extended | Paper 22 | May/Jun 2023 | Q23 | 1 mark | A |
| MCQ | Extended | Paper 23 | May/Jun 2023 | Q23 | 1 mark | C |
| MCQ | Extended | Paper 21 | May/Jun 2024 | Q22 | 1 mark | B |
| MCQ | Extended | Paper 21 | May/Jun 2024 | Q23 | 1 mark | B |
| MCQ | Extended | Paper 23 | May/Jun 2024 | Q23 | 1 mark | A |
| MCQ | Extended | Paper 21 | May/Jun 2024 | Q24 | 1 mark | A |
| MCQ | Extended | Paper 23 | May/Jun 2024 | Q24 | 1 mark | B |
| MCQ | Extended | Paper 23 | May/Jun 2024 | Q25 | 1 mark | D |
| MCQ | Extended | Paper 23 | May/Jun 2024 | Q26 | 1 mark | B |
| MCQ | Extended | Paper 23 | May/Jun 2024 | Q27 | 1 mark | D |
| MCQ | Extended | Paper 22 | Oct/Nov 2023 | Q19 | 1 mark | A |
| MCQ | Extended | Paper 23 | Oct/Nov 2023 | Q19 | 1 mark | C |
| MCQ | Extended | Paper 22 | Oct/Nov 2023 | Q20 | 1 mark | A |
| MCQ | Extended | Paper 23 | Oct/Nov 2023 | Q20 | 1 mark | D |
| MCQ | Extended | Paper 22 | Oct/Nov 2023 | Q21 | 1 mark | C |
| MCQ | Extended | Paper 23 | Oct/Nov 2023 | Q21 | 1 mark | C |
| MCQ | Extended | Paper 21 | Oct/Nov 2023 | Q22 | 1 mark | A |
| MCQ | Extended | Paper 22 | Oct/Nov 2023 | Q22 | 1 mark | C |
| MCQ | Extended | Paper 21 | Oct/Nov 2023 | Q23 | 1 mark | C |
| MCQ | Extended | Paper 22 | Oct/Nov 2023 | Q23 | 1 mark | C |
| MCQ | Extended | Paper 21 | Oct/Nov 2023 | Q24 | 1 mark | C |
| Theory | Core | Paper 32 | Mar 2023 | Q2 | 9 marks | (change) chemical AND |
| Theory | Core | Paper 32 | Mar 2024 | Q5 | 9 marks | (grey shading) nitrogen |
| Theory | Core | Paper 32 | May/Jun 2023 | Q2 | 10 marks | (concentrated) high ratio of, solute / sodium chloride / ions, to solvent / wate… |
| Theory | Core | Paper 32 | May/Jun 2023 | Q5 | 8 marks | (physical property) high density / high melting point / electrical conductor / h… |
| Theory | Core | Paper 33 | May/Jun 2023 | Q5 | 10 marks | magnesium oxide + sulfuric acid magnesium sulfate + water ; |
| Theory | Core | Paper 31 | May/Jun 2023 | Q8 | 8 marks | sulfuric (acid) AND water |
| Theory | Core | Paper 33 | May/Jun 2024 | Q2 | 9 marks | oxygen |
| Theory | Core | Paper 31 | May/Jun 2024 | Q8 | 5 marks | time |
| Theory | Core | Paper 33 | May/Jun 2025 | Q5 | 8 marks | (add UI to the acid and) look at the colour / state acid gives red colour |
| Theory | Core | Paper 31 | Oct/Nov 2023 | Q2 | 9 marks | test (anhydrous) copper sulfate |
| Theory | Core | Paper 31 | Oct/Nov 2023 | Q8 | 9 marks | (2,) 8, 7 |
| Theory | Extended | Paper 42 | Mar 2023 | Q5 | 10 marks | solute: (solid) magnesium sulfate |
| Theory | Extended | Paper 43 | May/Jun 2024 | Q5 | 9 marks | zinc sulfate |
| Theory | Extended | Paper 42 | May/Jun 2024 | Q8 | 9 marks | hydrogen / H |
| Theory | Extended | Paper 42 | Oct/Nov 2023 | Q2 | 8 marks | hydrochloric (acid) |
| Theory | Extended | Paper 42 | Oct/Nov 2023 | Q5 | 9 marks | magnesium AND |