Acids, bases and salts — IGCSE Chemistry (0971) questions by topic
Acids, bases and salts questions ask you to identify the reactants needed to make a named salt such as copper(II) sulfate, name which purification process would not suit an insoluble salt like lead(II) sulfate, work through preparing pure potassium sulfate crystals from potassium carbonate and sulfuric acid, and compare dissociation between two acids from given data. State, identify and name want precise, short factual answers, while describe and calculate cover method and numerical reasoning.
14 questions from 2025 papers make up this page, worth from 1 to 14 marks. Because salt-preparation questions are marked on the correct sequence of named steps, such as crystallisation or filtration in the right order, submitting a described method for instant marking checks whether a step has been left out or placed in the wrong order before that gap costs marks across the whole preparation.
May–June 2025, Paper 11
Which row gives the colours observed when thymolphthalein and methyl orange are added separately to the named solution? solution colour with thymolphthalein colour with methyl…
Answer this question and get it marked →A mixture of two substances, R and S, is heated gently. A diagram shows a test-tube containing R and S being heated with gentle heat, with a piece of damp red litmus paper held at…
Answer this question and get it marked →Which reactants are used to make the salt copper(II) sulfate? A dilute acid + alkali B dilute acid + metal carbonate C dilute acid + metal D dilute acid + non-metal oxide
Answer this question and get it marked →May–June 2025, Paper 12
Which row describes an aqueous solution for the pH shown? pH description --- --- --- A 1 has a very high alkalinity B 5 is neutral C 9 turns universal indicator yellow D 14…
Answer this question and get it marked →Which parts of the Periodic Table contain elements that only form basic oxides? A Group I and Period 3 B Group I only C Group VIII and Period 3 D Group VIII only
Answer this question and get it marked →May–June 2025, Paper 21
Two experiments involving acids R or S are done. - 0.10 mol of acid R completely dissolves in 500 cm^3 of water. 0.0048 mol of acid R is dissociated in the solution. - 0.10 mol of…
Answer this question and get it marked →Lead(II) sulfate is an insoluble salt. Which process is not used to prepare a pure sample of this salt? A crystallisation B drying C filtration D precipitation
Answer this question and get it marked →The formulae of two hydrated salts are shown. - CuSO4.xH2O - CoCl2.yH2O What are the values of x and y? The options give x and y: A x = 5, y = 5 B x = 5, y = 6 C x = 6, y = 5 D x…
Answer this question and get it marked →May–June 2025, Paper 22
A farmer incorrectly adds two substances to the soil at the same time. They react together to form a gas which turns damp red litmus paper blue. What are the two substances? A a…
Answer this question and get it marked →Which row shows the equations for the dissociation of hydrochloric acid and of ethanoic acid in aqueous solution? hydrochloric acid ethanoic acid --- --- --- A HCl(aq) - H^+(aq) +…
Answer this question and get it marked →May–June 2025, Paper 31
This question is about ionic and covalent compounds. Complete the word equation to show the reaction between magnesium carbonate and nitric acid. magnesium carbonate + nitric acid…
Answer this question and get it marked →May–June 2025, Paper 32
This question is about sea water and the substances found in sea water. Table 2.1 shows the masses of some of the compounds formed when 500 cm3 of sea water is evaporated. Table…
Answer this question and get it marked →May–June 2025, Paper 41
A list of substances is shown: bauxite, calcium oxide, ethanol, graphite, methane, nitrogen, oxygen, propane, propene, sulfur dioxide. Each substance may be used once, more than…
Answer this question and get it marked →May–June 2025, Paper 61
A student prepares some crystals of pure potassium sulfate by reacting aqueous potassium carbonate with dilute sulfuric acid. The equation for the reaction is shown. K2CO3(aq) +…
Answer this question and get it marked →