Identification of ions and gases: past paper questions

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• Question 40May/June 2026, paper 11Multiple choice1 mark

  Aqueous X reacts with aqueous $\mathrm{N}\mathrm{a}\mathrm{O}\mathrm{H}$ to produce a white precipitate that is soluble in excess aqueous $\mathrm{N}\mathrm{a}\mathrm{O}\mathrm{H}$. Aqueous X reacts with acidified aqueous $\mathrm{B}\mathrm{a}({\mathrm{N}\mathrm{O}}_3{)}_2$ to produce a white precipitate. What is X?

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• Question 39Oct/Nov 2025, paper 11Multiple choice1 markHas a diagram

  Two different white solids are heated and the gases formed are tested. The gas from solid 1 turns damp red litmus paper blue. The gas from solid 2 relights a glowing splint.

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• Question 40Oct/Nov 2024, paper 11Multiple choice1 mark

  The results of two tests on substance G are listed. ● A flame test produces a yellow flame. ● Substance G is added to aqueous sodium hydroxide and powdered aluminium and warmed carefully.

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• Question 40Oct/Nov 2023, paper 11Multiple choice1 markHas a diagram

  The results of two tests on aqueous compound X are given. | test | result | |---|---| | warm with aluminium foil and aqueous sodium hydroxide | ammonia is produced | | aqueous sodium hydroxide | brown precipitate | What is X?

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• Question 39May/June 2026, paper 12Multiple choice1 mark

  Which statement about chlorine gas is correct?

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• Question 40Oct/Nov 2025, paper 11Multiple choice1 mark

  Which aqueous ion gives a blue precipitate when aqueous sodium hydroxide is added?

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• Question 40Oct/Nov 2024, paper 21Multiple choice1 mark

  X is a white powder.

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• Question 40Oct/Nov 2023, paper 12Multiple choice1 markHas a diagram

  The results of tests on three gases, X, Y and Z, are shown.

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• Question 39Oct/Nov 2025, paper 12Multiple choice1 markHas a diagram

  The table shows the observations of two tests on an aqueous solution of a solid.

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• Question 40Oct/Nov 2024, paper 22Multiple choice1 markHas a diagram

  Which row describes a test and the observation for aqueous sulfate ions?

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• Question 31Oct/Nov 2023, paper 13Multiple choice1 markHas a diagram

  Two tests are done on an NPK fertiliser. test 1 flame test test 2 heat with aqueous sodium hydroxide and aluminium foil Which observations are made?

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• Question 11May/June 2026, paper 13Multiple choice1 mark

  Substance X is electrolysed.

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• Question 39Oct/Nov 2025, paper 13Multiple choice1 mark

  An aqueous cation reacts with aqueous sodium hydroxide to form a white precipitate. The precipitate is insoluble in excess sodium hydroxide. What is the aqueous cation?

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• Question 40Oct/Nov 2024, paper 23Multiple choice1 mark

  Which statement describes how a flame test is done?

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• Question 40Oct/Nov 2023, paper 13Multiple choice1 mark

  The results of some tests on an aqueous solution of substance X are listed. 1 A cream precipitate is produced when adding aqueous silver nitrate. 2 Adding aqueous sodium hydroxide produces a green precipitate which dissolves in excess alkali.

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• Question 39May/June 2026, paper 21Multiple choice1 mark

  Solution $\text{X}$ contains aqueous sulfite ions. Which method describes the test for the aqueous sulfite ions in $\text{X}$?

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• Question 1Oct/Nov 2024, paper 31Structured8 marksHas a diagram

  Fig. 1.1 shows part of the Periodic Table. Answer the following questions using only the elements in Fig. 1.1. Each symbol of the element may be used once, more than once or not at all.

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• Question 39Oct/Nov 2025, paper 21Multiple choice1 markHas a diagram

  The results of flame tests on three metal salts, X, Y and Z, are shown.

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• Question 5Oct/Nov 2024, paper 31Structured11 marks

  Table 5.1 shows some properties of five halogens. Use the information in Table 5.1 to predict: the melting point of iodine

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• Question 40May/June 2026, paper 23Multiple choice1 markHas a diagram

  Which row shows the reagents that are used to test for the chloride ion and for the sulfate ion?

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• Question 39Oct/Nov 2025, paper 23Multiple choice1 markHas a diagram

  Substance X contains one cation. Two tests are completed on aqueous X. test 1 flame test test 2 addition of aqueous sodium hydroxide dropwise and then in excess Which row shows a possible combination of observations for the tests?

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• Question 5Oct/Nov 2024, paper 32Structured11 marks

  Table 5.1 shows some properties of five halogens. Use the information in Table 5.1 to predict: the boiling point of iodine

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• Question 3Oct/Nov 2023, paper 31Structured12 marks

  Table 3.1 shows the average concentrations, in $\mathrm{n}\mathrm{g}\mathrm{/}1000{\mathrm{c}\mathrm{m}}^3$, of air pollutants in four different years. Name the pollutant that has the lowest concentration in 2019.

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• Question 7May/June 2026, paper 31Structured10 marks

  State the percentage of clean, dry air that is nitrogen.

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• Question 1Oct/Nov 2025, paper 31Structured5 marksHas a diagram

  Fig. 1.1 shows part of the Periodic Table. Fig. 1.1 Answer the following questions using only the symbols of the elements in Fig. 1.1. Each symbol may be used once, more than once or not at all.

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• Question 1Oct/Nov 2024, paper 33Structured8 marksHas a diagram

  Fig. 1.1 shows part of the Periodic Table. Fig. 1.1 Answer the following questions using only the elements in Fig. 1.1. Each symbol of the element may be used once, more than once or not at all.

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• Question 3Oct/Nov 2023, paper 32Structured12 marks

  Table 3.1 shows the average concentrations, in $\text{ng}\mathrm{/}1000{\text{cm}}^3$, of air pollutants in four different years. Table 3.1 Name the oxide pollutant that has the highest concentration in 2021.

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• Question 2May/June 2026, paper 32Structured10 marksHas a diagram

  Table 2.1 shows some properties of the Group I elements. Table 2.1 Use the information in Table 2.1 to answer the following questions. Predict the melting point of sodium.

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• Question 3Oct/Nov 2025, paper 31Structured9 marksHas a diagram

  Table 3.1 shows the masses of ions, in mg, present in a $1000{\text{ cm}}^3$ sample of river water. Table 3.1 Answer these questions using the information from Table 3.1. Name the positive ion that has the highest concentration.

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• Question 1Oct/Nov 2024, paper 42Structured9 marks

  The formulae of the molecules A to I are shown in Table 1.1.

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