Chemistry Test Paper
The volume of one mole of any gas is 24 dm3 at room temperature and pressure.
Ar: H = 1; C = 12; O = 16; Al = 27; Cl = 35.5; K = 39; Ca = 40; Ti = 48
1 What mass of hydrogen gas is produced when 8.1 g of aluminium powder reacts with excess
dilute hydrochloric acid according to the equation
[Total: 3 marks]
2 What volume of oxygen gas, O2(g), is produced at room temperature and pressure when 0.142
g of potassium superoxide, KO2(s), reacts with excess carbon dioxide, CO2(g), according to
the equation
[Total: 3 marks]
3 What mass of calcium carbide, CaC2 (s), is required to produce 120 cm3 of ethyne gas, C2H2
(g), by reaction with excess water according to the equation.
[Total: 3 marks]
4 20.0 cm3 of aqueous KOH neutralised 35.0 cm3 of dilute sulfuric acid, H2SO4 (aq), whose
concentration was 0.20 mol dm−3. The equation is
Calculate the concentration of the aqueous potassium hydroxide, KOH(aq), in
a mol dm−3
b g dm−3
[Total: 4 marks]
5 A compound has composition by mass which is 54.5% carbon, 9.1% hydrogen and 36.4%
oxygen.
The Mr of the compound = 44. Calculate the
a empirical formula
b molecular formula of the compound.
[Total: 4 marks]
6 When 0.38 g of titanium (IV) chloride, TiCl4 (s), reacted with excess sodium, the reaction
produced 0.024 g of titanium, Ti(s). The equation is
Calculate the percentage yield of titanium.
[Total: 4 marks]