Question

Making use only of substances chosen from those given below:

Dilute sulphuric acid

Sodium carbonate

Zinc

Sodium sulphite

Lead

Salcium carbonate

Give the equation for the reaction by which you could obtain:

1. Hydrogen
2. Sulphur dioxide
3. Carbon dioxide
4. Zinc Carbonate (two steps required).

From the substances given in the list below, write the equations for the reactions by which you could obtain the compounds given ahead:

\[ \begin{array}{|l|l|} \hline \text{Dilute sulphuric acid} & \text{sodium carbonate} \\ \hline \text{Zinc} & \text{sodium sulphite} \\ \hline \text{Lead} & \text{calcium carbonate} \\ \hline \end{array} \]

1. hydrogen,
2. sulphur dioxide,
3. carbon dioxide,
4. zinc carbonate (two steps required).

Answer 1

1. Zinc reacts with dilute sulphuric acid to evolve hydrogen.
   \[\ce{Zn + H2SO4 → ZnSO4 + H2 ^}\]
2. Sodium sulphite reacts with dilute sulphuric acid to give sulphur dioxide.
   \[\ce{Na2SO3 + H2SO4 -> Na2SO4 + H2O + SO2 ^}\]
3. Sodium carbonate reacts with dilute sulphuric acid to give carbon dioxide.
   \[\ce{Na2CO3 + H2SO4 -> Na2SO4  + H2O + CO2 ^}\]
4. Zinc reacts with dilute sulphuric acid to form zinc sulphate, which in reaction with sodium carbonate forms zinc carbonate.
   \[\ce{ Zn + H2SO4 -> ZnSO4 + H2 ^}\]
   \[\ce{ZnSO4 + Na2CO3 -> ZnCO3 + Na2SO4}\]