Chemical reactions — IGCSE Physical Science (0652) questions by topic
Chemical reactions questions cover extracting lead using carbon monoxide, identifying which conditions speed up the reaction between marble chips and hydrochloric acid, and measuring the volume of carbon dioxide produced every 30 seconds. State, identify, explain and describe are the command words, with explain wanting the reasoning behind oxidation and reduction rather than just naming the products.
6 real questions from 2023 papers make up this page, worth 1 to 10 marks. Rate-of-reaction answers are marked on naming a genuinely different measuring method and describing results precisely, so submitting your responses for instant marking helps you see whether a suggested method, such as measuring gas volume, has actually been distinguished from one already given in the question.
What examiners look for
- A recurring mistake is suggesting counting bubbles, which is only another way of measuring gas volume rather than a genuinely different method, and describing a lit or relit splint test instead of the limewater test.
- Examiners also flag candidates saying to measure the temperature without stating that it increases, writing correct formulae with reactants and products swapped, and incorrectly linking carbon dioxide to damage of the ozone layer.
October–November 2023, Paper 21
The rate of reaction between marble chips and hydrochloric acid is investigated. The equation is shown. CaCO₃(s) + 2HCl(aq) → CaCl₂(aq) + H₂O(l) + CO₂(g) Which conditions give the…
Answer this question and get it marked →Lead is extracted from its ore using carbon monoxide. The equation is shown. PbO + CO → Pb + CO₂ Which statement explains what happens to the lead atoms and carbon atoms in the…
Answer this question and get it marked →October–November 2023, Paper 22
The rate of reaction between marble chips and hydrochloric acid is investigated. The equation is shown. CaCO₃(s) + 2HCl(aq) → CaCl₂(aq) + H₂O(l) + CO₂(g) Which conditions give the…
Answer this question and get it marked →Lead is extracted from its ore using carbon monoxide. The equation is shown. PbO + CO → Pb + CO₂ Which statement explains what happens to the lead atoms and carbon atoms in the…
Answer this question and get it marked →October–November 2023, Paper 31
A student measures the rate of the reaction between pieces of calcium carbonate and excess dilute hydrochloric acid; carbon dioxide gas is produced. The student measures the…
Answer this question and get it marked →October–November 2023, Paper 32
A student measures the rate of the reaction between pieces of calcium carbonate and excess dilute hydrochloric acid; carbon dioxide gas is produced. The student measures the…
Answer this question and get it marked →