Assertion: Photochemical smog is oxidising in nature.
Reason: Photochemical smog contains `NO_(2)` and `O_(3)` which are formed during the sequence of reactions.

Options

A. Both A and R are correct and R is the correct explanation of A
B. Both A and R are correct and R is not the correct explanation of A
C. Both A and R are not correct
D. A is not correct but R is correct

Answer

A

Explanation

Both assertion and reason are correct and reason is the correct explanation of assertion. When fossil fuel are burnt, a veriety of pollutes are emitted into the earth's troposphere. Two of the pollutants that are emitted hydrocarbons (unburnt fuels) and nitric oxide (NO).
When these pollutes build up to sufficiently high levels, a chain reaction occurs from their ineractions with sun light in which NO oxidises to`NO_(2)`. in turns absorbs energy from sunlight and breaks up into nitric oxide and free oxygen atom.
`NO_(2)(g) overset(hv)rarrNO(g) + O(g)`
Oxygen atoms are very reactive and combine with `O_(2)` in produce ozone.
`O(g) + O_(2)(g) hArr O_(3)(g)`