Question

Which among the following acts as oxidising as well as reducing agent?

• A. $HN{O}_2$
• B. $HN{O}_3$
• C. $H_{2}S{O}_4$
• D. $KMn{O}_4$

Answer 1

The correct option is A $HN{O}_2$

Substance can acts as oxidising as well as reducing agent when it is present in its intermediate oxidation state.

Nitrogen in $HN{O}_2$ is present in +3 oxidation state which is its intermediate state so it can acts as oxidising as well as reducing agent.

Nitrogen in $HN{O}_3$ is present in +5 oxidation state which is its highest oxidation state so it cannot act as reducing agent.

Sulphur in $H_{2}S{O}_4$ is present in +6 oxidation state which is its highest oxidation state so it cannot act as reducing agent.

$Mn$ in $KMn{O}_4$ is present in +7oxidation state which is its highest oxidation state so it cannot act as reducing agent.