CHEMISTRY FORM 5 REVISION

The diagram below shows four test tubes that contain different metals immersed in water.

Which metal has the highest rate of corrosion?

• Magnesium

• Copper

• Zinc

• Tin

Which of the following reactions occurs in the experiment, as shown in the diagram below?

• Iron(III) ions are oxidised

• Iron(III) ions donate electrons

• Zinc atoms gain electrons

• Zinc acts as a reducing agent

Which of the following reactions shows the greatest increase in the oxidation number of nitrogen?

• NH₃(g) + HCl(g) → NH₄Cl(s)

• 2NH₃(g) + 3CuO(s) → N₂(g) + 3Cu(s) + 3H₂O(l)

• 2NO(g) + O₂(g) → 2NO₂(g)

• 4NO₂(g) + O₂(g) + 2H₂O(l) → 4HNO₃(aq)

Which of the following conversion undergoes a reduction reaction?

• Chloride ion to chlorine gas

• Lead(II) ion to lead atom

• Hydrogen sulphide to sulphur

• Iron(II) ion to iron(III) ion

In the dark, compound W can react with chlorine gas to produce an organic compound as shown below.

What is compound W?

• Pent-1-ene

• Pent-2-ene

• Pent-3-ene

• Pentane

The following are the properties of compound X.

• Insoluble in water
• Has a boiling point of -42.1°C

Which of the following is compound X?

• Propane

• Propanol

• Propanoic acid

• Propyl propanoate

During an incomplete combustion, which of the following compounds will produce the highest amount of soot?

[Relative atomic mass: H = 1, C = 12, O = 16]

• C₂H₅OH

• C₇H₁₆

• C₄H₈

• C₃H₇COOH

How many isomers for butanol?

• 3

• 4

• 5

• 6

The thermochemical ionic equation below represents the reaction between magnesium powder and iron(II) sulphate solution.

Mg(s) + Fe²⁺(aq) → Mg²⁺(aq) + Fe(s)     ΔH = -189 kJ mol^-1

What is the temperature increase when excess magnesium powder is added to 80 cm³ of 0.4 mol dm^–3 iron(II) sulphate solution?

[Specific heat capacity of solution = 4.2 J g^–1 °C^–1; Density of solution = 1 g cm^–3]

• 6.5°C

• 13.5°C

• 18.0°C

• 37.8°C

The thermochemical equation for the reaction between magnesium and iron(II) chloride solution is shown below.

Mg + FeCl₂ → MgCl₂ + Fe     ΔH = -201.6 kJ mol^-1
What is the heat change when 2.8 g of iron is formed in this reaction? 
[Relative atomic mass: Fe, 56]

• 1.08 kJ

• 10.08 kJ

• 11.30 kJ

• 56.4 kJ