Question

Assertion (A): Photochemical smog is oxidising in nature.

Reason (R): Photochemical smog contains NO₂ and O₃, which are formed during the sequence of reactions.

पर्याय

• Both A and R are correct and R is the correct explanation of A.

• Both A and R are correct but R is not the correct explanation of A.

• Both A and R are not correct.

• A is not correct but R is correct.

Answer 1

Both A and R are correct and R is the correct explanation of A.

Explanation:

Since a photochemical smog has high concentration of oxidizing agents and is known as oxidizing smog. Two of the pollutants that are emitted are hydrocarbons (unburned fuels) and nitric oxide (NO). When these pollutants build up to sufficiently high levels, a chain reaction occurs from their interaction with sunlight in which NO is converted into nitrogen dioxide and this in turn absorbs energy from the sunlight and breaks up into nitric oxide and free oxygen atoms. This is shown as-

\[\ce{NO2 (g) ->[hv] NO (g) + O (g)}\]

\[\ce{O (g) + O2 (g) -> O3 (g)}\]