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Q.
The reaction, $P_{4} + NaOH + H_{2}O\to NaH_{2}PO_{2}+ PH_{3}$ is
Redox Reactions
Solution:
$\overset{0}{P_{4}}+NaOH+H_{2}O \to NaH_{2}\overset{+1}{P}O_{2}+\overset{-3}{P}H_{3}$
In the given reaction $P_{4}$ is both oxidised $(\overset{0}{P_{4}} \to NaH_{2}\overset{+1}{P}O_{2})$
as well as reduced $(\overset{0}{P_{4}} \to \overset{-3}{P}H_{3})$