(a) A student dropped a few pieces of marble in dilute hydrochloric acid contained in
a test tube. The evolved gas was passed through lime water. What change would
be observed in lime water ? Write balanced chemical equations for both the
changes observed.
(b) State the chemical property in each case on which the following uses of baking
soda are based:
(i) as an antacid (ii) as a constituent of baking powder.

Explanation

### Step-by-Step Solution

#### Part (a)

1. **Identify the Reactants**:
- The student dropped pieces of marble, which is calcium carbonate (CaCO₃), into dilute hydrochloric acid (HCl).

2. **Write the Reaction**:
...