Question

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. [3 MARKS]

Answer 1

Each point: 1.5 Mark

1. It is weakly alkaline in nature and neutralizes acid (HCl) formed in the stomach. The reaction involved is

${\text{NaHCO}}_3+\text{HCl}\to \text{NaCl}+{\text{H}}_2\text{O}+{\text{CO}}_2$

2. It evolves ${\text{CO}}_2$ in the form of bubbles when cake is made by baking. As a result, the cake becomes porous as well as fluffy. The reaction involved is

${\text{NaHCO}}_3\to {\text{Na}}_2{\text{CO}}_3+{\text{H}}_2\text{O}+{\text{CO}}_2$