Identification of Ions & Gases (Cambridge (CIE) IGCSE Combined Science: Chemistry): Exam Questions

Exam code: 0653

8 mins3 questions
1
3 marks

Iron(II) ions, Fe2+, are formed from atoms of iron, Fe.

(i) Describe how Fe2+ ions are formed from iron atoms.

[1]

(ii) Describe what is observed when aqueous sodium hydroxide is added to aqueous iron(II) ions.

[2]

2
2 marks

You are going to investigate the reaction between metal F and dilute sulfuric acid.

(a) Procedure:

  • Add 3 cm depth of dilute sulfuric acid to a clean test-tube.

  • Add a spatula of metal F to the test-tube.

  • Test the gas produced in the reaction to identify it.

(i) State the test used to identify the gas and give the observation for a positive result.

[1]

(ii) State the name of the gas.

[1]

3
3 marks

A student investigates the reaction between metal F and dilute sulfuric acid.

(i) Procedure

The student:

  • adds 3 cm depth of dilute sulfuric acid to a test-tube

  • adds a spatula of metal F to the test-tube

  • observes the mixture fizzing slowly

  • tests the gas produced with a lighted splint

  • hears a squeaky pop.

Identify the gas produced.

[1]

(ii) The student repeats the procedure from (a)(i) but also adds aqueous copper(II) sulfate to the dilute sulfuric acid and metal F.

The student observes that this reaction is faster than the reaction in (a)(i).

Suggest one observation the student makes which shows that this reaction is faster.

[1]

(iii)

Procedure

The student:

  • pours a small volume of the aqueous product from the procedure in (a)(i) into a test‑tube

  • adds aqueous sodium hydroxide

  • observes a white precipitate.

Use this observation to suggest two possible identities for the cation produced from metal F.

[1]