Question

Write a balanced equation for the preparation of each of the following salts.

(i) Copper sulphate from Copper carbonate

(ii) Zinc carbonate from Zinc sulphate

Answer 1

Part 1: Copper sulphate from Copper carbonate

1. Copper carbonate when treated with Sulphuric acid forms Copper sulphate.
2. $\underset{(\mathrm{Copper}\mathrm{carbonate})}{{\mathrm{CuCO}}_3\left(\mathrm{aq}\right)}+\underset{(\mathrm{Sulphuric}\mathrm{acid})}{{\mathrm{H}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)}\to \underset{(\mathrm{Copper}\mathrm{sulphate})}{{\mathrm{CuSO}}_4\left(\mathrm{aq}\right)}+\underset{\left(\mathrm{Water}\right)}{{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}+\underset{(\mathrm{Carbon}\mathrm{dioxide})}{{\mathrm{CO}}_2\left(\mathrm{g}\right)}$

Part 2: Zinc carbonate from Zinc sulphate

1. A double displacement reaction in which Zinc sulphate is combined with Sodium carbonate to produce Sodium sulphate and a white ppt of Zinc carbonate.
2. $\underset{(\mathrm{Zinc}\mathrm{sulphate})}{{\mathrm{ZnSO}}_4\left(\mathrm{aq}\right)}+\underset{(\mathrm{Sodium}\mathrm{carbonate})}{{\mathrm{Na}}_2{\mathrm{CO}}_3\left(\mathrm{aq}\right)}\to \underset{(\mathrm{Sodium}\mathrm{sulphate})}{{\mathrm{Na}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)}+\underset{(\mathrm{Zinc}\mathrm{carbonate})}{{\mathrm{ZnCO}}_3\left(\mathrm{s}\right)(\downarrow )}$

Hence, the balanced equations are as follows

(i) $\underset{(\mathrm{Copper}\mathrm{carbonate})}{{\mathrm{CuCO}}_3\left(\mathrm{aq}\right)}+\underset{(\mathrm{Sulphuric}\mathrm{acid})}{{\mathrm{H}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)}\to \underset{(\mathrm{Copper}\mathrm{sulphate})}{{\mathrm{CuSO}}_4\left(\mathrm{aq}\right)}+\underset{\left(\mathrm{Water}\right)}{{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}+\underset{(\mathrm{Carbon}\mathrm{dioxide})}{{\mathrm{CO}}_2\left(\mathrm{g}\right)}$

(ii) $\underset{(\mathrm{Zinc}\mathrm{sulphate})}{{\mathrm{ZnSO}}_4\left(\mathrm{aq}\right)}+\underset{(\mathrm{Sodium}\mathrm{carbonate})}{{\mathrm{Na}}_2{\mathrm{CO}}_3\left(\mathrm{aq}\right)}\to \underset{(\mathrm{Sodium}\mathrm{sulphate})}{{\mathrm{Na}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)}+\underset{(\mathrm{Zinc}\mathrm{carbonate})}{{\mathrm{ZnCO}}_3\left(\mathrm{s}\right)(\downarrow )}$