Question 05.
Sodium carbonate is a basic salt because it is a salt of
(a) strong acid and strong base
(b) weak acid and weak base
(c) strong acid and weak base
(d) weak acid and strong base

Sodium carbonate $\left({\text{Na}}_2{\text{CO}}_3\right)$ is a salt formed when weak acid like carbonic acid $\left({\text{H}}_2{\text{CO}}_3\right)$ and a strong base like sodium hydroxide (NaOH) combines.

$\underset{\text{sodium hydroxide}}{\text{2NaOH}}+\underset{\text{carbonic acid}}{{\text{H}}_2{\text{CO}}_3}⟶\underset{\text{sodium carbonate (salt)}}{{\text{Na}}_2{\text{CO}}_3}+\underset{\text{water}}{2{\text{H}}_2\text{O}}$