Question

Assertion (A): Nitric acid prepared in the laboratory is yellow in colour.

Reason (R): Brown gas is used in its preparation.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Options

• (1)

• (2)

• (3)

• (4)

Answer 1

(3)

Explanation:

Nitric acid prepared in the laboratory may appear yellow because some of it decomposes on exposure to light or heat and forms nitrogen dioxide (NO₂), which dissolves in the acid. Therefore, the Assertion (A) is true.

The brown gas, nitrogen dioxide, is not used as a reactant in the laboratory preparation of nitric acid. It is formed due to partial decomposition of nitric acid. Therefore, the Reason (R) is false.

Hence, A is true and R is false.