Question

Identify the correct sequence of denitrification

• A. $N_2\to NO\to N{O}_2^{}\to N{O}_3^{-}$
• B. $N_2\to N{O}_2^{}\to N{O}_3^{-}\to N{O}_4^{-}$
• C. $N{O}_3^{-}\to N{O}_2^{}\to NO\to N{H}_4^{+}$
• D. $N{O}_3^{-}\to N{O}_2^{-}\to NO\to N{O}_2$

Answer 1

The correct option is D

$N{O}_3^{-}\to N{O}_2^{-}\to NO\to N{O}_2$

Nitrate present in the soil is anaerobically reduced to nitrogen by a process called denitrification. It is the final step of the cycle where atmospheric nitrogen utilised for the cycle is recycled back to the atmosphere itself.