1. Iron(II) sulphide reacts with hydrochloric acid as follows:
FeS(s) + 2HCl(aq) à FeCl2(aq) + H2S(g)
If 4.4g of iron(II) sulphide was added to 160cm3 of 0.5 mol l-1 hydrochloric acid, show by calculation which substance is in excess.
2. A student added 0.20g of silver nitrate, AgNO3, to 25 cm3 of water. This solution was then added to 20cm3 of 0.0010 mol l-1 hydrochloric acid. The equation for the reaction is:
AgNO3(aq) + HCl(aq) à AgCl(s) + HNO3(aq)
Show by calculation which reactant is in excess.
3. Calcite is a very pure form of calcium carbonate which reacts with nitric acid as follows:
CaCO3(s) + 2HNO3(aq) à Ca(NO3)2(aq) + H2O(l) + CO2(g)
A 2.14g piece of calcite was added to 50.0cm3 of 0.200 mol l-1 nitric acid in a beaker.
Calculate the mass of calcite, in grams, left unreacted.
4. Copper(II) oxide reacts with sulphuric acid as follows:
CuO(s) + H2SO4(aq) à CuSO4(aq) + H2O(l)
1.6 g of copper(II) oxide is added to a beaker containing 50cm3 of 0.25 mol l-1 sulphuric acid.
Calculate the mass of copper(II) oxide remaining after the reaction was complete.
5. Lead reacts with hydrochloric acid as follows:
Pb(s) + 2HCl(aq) à PbCl2(aq) + H2(g)
If 6.22g of lead was added to 50cm3 of 1 mol l-1 hydrochloric acid, calculate the mass of lead left unreacted.
6. A strip of zinc metal weighing 2.00 g is placed in an aqueous solution containing 10.00 g of silver nitrate. The reaction that occurs is
Zn(s) + 2AgNO3(aq) à 2Ag(s) + Zn(NO3)2(aq)
(a) Determine which reactant is in excess.
(b) Calculate how many grams of silver will be formed.
7. A piece of lithium with a mass of 1.50 g is placed in an aqueous solution containing 6.00 g of copper (II) sulphate. The reaction that occurs is:
2Li(s) + CuSO4(aq) à Cu + Li2SO4 (aq)
(a) Determine which reactant is in excess.
(b) Calculate how many grams of copper will be formed.
