Question

When P reacts with caustic soda, the products are $P{H}_3$ and $Na{H}_{2}P{O}_2$. The reaction is an example of.

• A. Oxidation
• B. Reduction
• C. Both oxidation and reduction
• D. Neutralisation

Answer 1

Answer: (C)

Both oxidation and reduction

$P_4+3NaOH+3H_{2}O\to P{H}_3+3Na{H}_{2}P{O}_2$

In reactant P is present in (0) oxidation state and in $P{H}_3$, it is present in (-3) oxidation state and in $Na{H}_{2}P{O}_2$ it is present in (+1) oxidation state.

So $P$ undergoes both oxidation and reduction.