The Chemical Properties of the Halogen Elements & the Hydrogen Halides (Cambridge (CIE) A Level Chemistry): Exam Questions

Exam code: 9701

47 mins14 questions
1
1 mark

Aqueous iodine is added to aqueous potassium bromide.

Which statement describes the outcome?

  • Bromide ions are oxidised to bromine.

  • Iodine is oxidised to iodide ions.

  • No reaction occurs.

  • Potassium bromide is reduced to bromine.

2
1 mark

Chlorine gas is bubbled through aqueous potassium iodide.

Which statement describes the outcome?

  • Chlorine is oxidised to chlorate(V) ions.

  • Chlorine is oxidised to chloride ions.

  • Iodide ions are oxidised to iodine.

  • There is no observable reaction.

3
1 mark

Which halide ions act as reducing agents when solid sodium halides react with concentrated sulfuric acid?

  • Br and I only

  • Cl and Br only

  • Cl, Br and I

  • I only

1
1 mark

On being heated, hydrogen iodide breaks down more quickly than hydrogen chloride.

Which statement does not explain this difference in rate?

  • The activation energy for the decomposition of HI is lower than that of HCl.

  • The decomposition of HCl is more endothermic than the decomposition of HI.

  • The H–Cl bond is stronger than the H–I bond.

  • The H–I bond is longer than the H–Cl bond.

2
1 mark

On contact with a hot glass rod, which gaseous hydride most readily decomposes into its elements?

  • ammonia

  • hydrogen chloride

  • hydrogen iodide

  • steam

3
1 mark

When a hot platinum wire is plunged into a test tube of hydrogen chloride, no change occurs. However, if the experiment is repeated with hydrogen iodide, the gas is decomposed into its elements.

Which factor does not explain this observation?

  • the activation energy of the decomposition reaction

  • the difference in electronegativity between the hydrogen and halogen atoms

  • the size of the halogen atom

  • the strength of the hydrogen–halogen bond

4
1 mark

Which row correctly describes the observations when aqueous silver nitrate, followed by aqueous ammonia, is added to the specified halide ion?

Row

Halide ion

Colour of precipitate with AgNO3 (aq)

Observation on adding aqueous ammonia

A

Cl

white

dissolves in dilute aqueous ammonia

B

Br

white

dissolves in concentrated aqueous ammonia only

C

I

cream

remains insoluble in concentrated aqueous ammonia

D

Br

cream

dissolves in dilute aqueous ammonia

    1
    1 mark

    X, Y and Z represent different halogens. The table shows the results of nine experiments in which aqueous solutions of X2, Y2 and Z2 were added to separate aqueous solutions containing X, Y and Z ions.

    X (aq)

    Y (aq)

    Z (aq)

    X2 (aq)

    no reaction

    no reaction

    no reaction

    Y2 (aq)

    X2 formed

    no reaction

    Z2 formed

    Z2 (aq)

    X2 formed

    no reaction

    no reaction

    What is the correct order of decreasing strength of the ions X, Y and Z as reducing agents?

    • X > Y > Z

    • X > Z > Y

    • Y > Z > X

    • Z > X > Y

    2
    1 mark

    A dark red/brown solution is formed when a halide salt containing the halide ion Y- reacts with aqueous chlorine. This solution then forms a violet solution when shaken with a cyclohexane solution.

    What is halogen, Y?

    • bromide

    • fluorine

    • iodide

    • iodine

    3
    1 mark

    Which statement about Group 7 elements is not correct?

    • Astatine has a lower first ionisation energy than iodine.

    • Fluorine is the weakest reducing agent in Group 17.

    • Iodomethane produces a silver halide precipitate with aqueous silver nitrate in ethanol faster than chloromethane or bromomethane.

    • The bond dissociation energy of the hydrogen halides increases from HCl to HI.