Question

In a reaction, 3 moles of electrons are gained by 1 mole of $HN{O}_3$ assuming no change in O.N. of hydrogen and oxygen, the possible product obtained due to reduction will be

• A. 1 mole of $N{O}_2$
• B. 0.5 mole of $N{O}_2$
• C. 1 mole of NO
• D. 0.5 mole of $N_2{O}_3$

Answer 1

The correct option is C 1 mole of NO

1 mole of $HN{O}_3$ use 3 moles of electrons to get reduced where oxidation number of hydrogen and oxygen are not changed. Hence, oxidation number of N will change.
In $HN{O}_3$, oxidation state of N is +5
So it use 3 $e^{-}$ and get reduced to +2 oxidation state.
O.N. of N in the product = +5 - 3 = +2
Hence, the product is 1 mole of NO.