1.1. This question is about reactions involving calcium compounds.

Heating calcium carbonate, CaCO₃, produces calcium oxide, CaO, and one other gaseous product.

Write the word equation for this reaction.

1.2. Write a balanced chemical equation for heating calcium carbonate, CaCO₃, to form calcium oxide, CaO, and one other gaseous product.

1.3. Calcium hydroxide, Ca(OH)₂ can be made by the reaction of calcium oxide, CaO, with water.

CaO + H₂O → Ca(OH)₂ 

112 g of calcium oxide reacts with 36 g of water.

 Calculate the mass of calcium hydroxide that is produced.

____________________ g

1.4. Calcium hydroxide can be used to test for the presence of carbon dioxide.

If carbon dioxide is present, the calcium hydroxide will form a milky white precipitate of calcium carbonate.

The formula of calcium carbonate is CaCO₃

Calculate the relative formula mass (M_r) of calcium carbonate.

Relative atomic masses (A_r): C = 12   O = 16   Ca = 40

1.5. Calculate the percentage of oxygen in calcium carbonate, CaCO₃, using the following equation.

Percentage by mass = $\frac{{A}_{r}\timesnumberofatoms}{{M}_{r}ofthecompound}\times100$