Question

$1$ mole of $HN{O}_3$ absorbs $4$ moles of electrons in a redox reaction. The reduced product of this reaction is :

• A. $1$ mole $N_2$
• B. $1$ mole $N_{2}O$
• C. $1$ mole $N{O}_2$
• D. $1$ mole $N{H}_3$

Answer 1

The correct option is B $1$ mole $N_{2}O$

Oxidation state of $N$ in $HN{O}_3$ $=1+x+(3x-2)$

$=1+x-6$

$x-5$

$x=+5$

On addition of $4$ moles of electrons, it reduces to a $+1$ oxidation state i.e $N_{2}O$

Since, Oxidation state of $N$ in $N_{2}O=x-2=0$

$2x=2$

$x=+1$