IGCSE Coordinated Chemistry Revision

Iron(III) chromate is a yellow solid. It contains the ions Fe³⁺ and (CrO₄) ^2– .

What is the formula of iron(III) chromate?

• FeCrO₄

• Fe₃(CrO₄)₂

• Fe₂CrO₄

• Fe₂(CrO₄)₃

The diagram shows a circuit used to electrolyse aqueous copper(II) sulfate

Which arrows indicate the movement of the copper ions in the electrolyte and of the electrons in the external circuit?

• Copper ions - 1

  Electrons - 3

• Copper ions- 1

  Electrons - 4

• Copper ions- 2

  Electrons - 3

• Copper ions- 2

  Electrons - 4

Ethene burns in oxygen to form carbon dioxide and water vapour.

The bond energies are :

C=C : +610 kJ / mol

C–H : +410 kJ / mol

O=O: +497 kJ / mol

C=O: +805 kJ / mol

O–H : +460kJ / mol

What is the energy change for the reaction?

• –2959 kJ /mol

• –2313 kJ /mol

• –1319 kJ /mol

• –399 kJ /mol

The equation for the formation of ammonia is shown.

N₂ + 3H₂ → 2NH₃

The energy level diagram for the reaction is shown.

What is the energy change for the reaction?

• –592 kJ /mol

• –92 kJ / mol

• +92 kJ / mol

• +592 kJ / mol

Dilute hydrochloric acid reacts with 1 g of limestone.

Which conditions produce the fastest rate of reaction?

• 2 mol / dm³ hydrochloric acid and a single lump of limestone

• 4 mol / dm³ hydrochloric acid and a single lump of limestone

• 4 mol / dm³ hydrochloric acid and small pieces of limestone

• 4 mol / dm³ hydrochloric acid and powdered limestone

The equation for the reaction between zinc and copper(II) oxide is shown.

Zn + CuO → ZnO + Cu

Which row shows the oxidising agent and the reducing agent?

• A

• B

• C

• D

The results of some experiments with sulfur dioxide are shown.

Which results are correct?

• 1, 2 and 4

• 2, 3 and 4

• 1 and 2 only

• 3 and 4 only

Some general rules for the solubility of salts in water are listed.

● Carbonates are insoluble (except ammonium carbonate, potassium carbonate and sodium carbonate).

● Chlorides are soluble (except lead(II) chloride and silver chloride). ● Nitrates are soluble.

● Sulfates are soluble (except barium sulfate, calcium sulfate and lead(II) sulfate).

Which substances produce an insoluble salt when aqueous solutions of them are mixed?

• barium chloride and magnesium nitrate

• calcium chloride and ammonium nitrate

• silver nitrate and zinc chloride

• sodium carbonate and potassium sulfate

Elements in Group I of the Periodic Table react with water.

Which row describes the products made in the reaction and the trend in reactivity of the elements?

• A

• B

• C

• D

Heating a metal compound in a Bunsen flame turns the flame green.

Which metal ion is present in the compound?

• calcium

• copper

• potassium

• sodium