Question

Which of the following molecules can act as an oxidising agent as well as a reducing agent?

• A. $H_{2}S$
• B. $S{O}_3$
• C. $H_2{O}_2$
• D. $F_2$
• E. $H_{2}S{O}_4$

Answer 1

Answer: (C)

$H_2{O}_2$

A substance can act as oxidising as well as reducing agent when it is present in its intermediate oxidation state.

In $H_{2}S$, sulphur is present in -2i.e., its minimum oxidation state.So it cannot acts as oxidising agent.

In $S{O}_3$, sulphur is present in +6i.e., its maximum oxidation state.So it cannot acts as reducing agent.

In $H_2{O}_2$,oxygen is present in -1 oxidation state so it can acts as both oxidising as well as reducing agent.

$F_2$ cannot acts as reducing agent.

In $H_{2}S{O}_4$, sulphur is present in +6i.e., its maximum oxidation state.So it cannot acts as reducing agent.

So $H_2{O}_2$ can acts as both oxidising as well as reducing agent.