Question

Identify the oxidant and the reductant in the following reaction respectively:
$Cu+HN{O}_3\left(dil\right)\to Cu(N{O}_3{)}_2+H_{2}O+NO$

• A. $HN{O}_3$ $\&$ $NO$
• B. $NO$ $\&$ $HN{O}_3$
• C. $Cu$ $\&$ $HN{O}_3$
• D. $HN{O}_3$ $\&$ $Cu$

Answer 1

The correct option is D $HN{O}_3$ $\&$ $Cu$

$\stackrel{\left(0\right)}{Cu}+\stackrel{(+5)}{HN{O}_3\left(dil\right)}\to \stackrel{(+2)}{Cu}(N{O}_3{)}_2+H_{2}O+\stackrel{(+2)}{NO}.$
$\stackrel{\left(0\right)}{Cu}\left(\text{reductant}\right)\to \stackrel{(+2)}{Cu}(N{O}_3{)}_2\left(\text{oxidation half}\right).$
$\stackrel{(+5)}{HN{O}_3}\text{(oxidant)}\to \stackrel{(+2)}{NO}\left(\text{reduction half}\right).$
A species which gain electron in a redox reaction is called as reducing agent.
$\left(HN{O}_3\right)$ gets converted into nitric oxide $\left(NO\right)$. Nitrogen is getting reduced because it is gaining electrons or losing bonds to oxygen, so $HN{O}_3$ is the oxidizing agent.

A species which looses electron in a redox reaction is called as oxidising agent.
Cu gets converted to $C{u}^{2+}$ Cu is getting oxidized since there is loss of electrons , so it is the reducing agent.

$HN{O}_3$ and $Cu$ in this order is the correct answer.