Question

Which of the following is obtained on decomposition of moderately concentrated $HN{O}_3$

• A. $NO$
• B. $N_2{O}_3$
• C. $N_2{O}_4$
• D. $N_2{O}_5$

Answer 1

The correct option is A

$NO$

Moderately concentrated nitirc acid gives nitric oxide and nascent oxygen which is a monatomic oxygen radical, which is far more reactive.

$2HN{O}_3\to NO+3\left[O\right]+H_{2}O$

While highly concentrated nitric acid gives nitrogen dioxide and a nascent oxygen

$2HN{O}_3\to N{O}_2+\left[O\right]+H_{2}O$