White phosphorus is a translucent white waxy solid. It is poisonous, insoluble in water but soluble in carbon disulphide and glows in dark (chemiluminescence). It dissolves in boiling $\mathrm{NaOH}$ solution in an inert atmosphere giving ${\mathrm{PH}}_3$.

$$\begin{gathered} {\mathrm{P}}_4+3\mathrm{NaOH}+3{\mathrm{H}}_2\mathrm{O}\to {\mathrm{PH}}_3+3{\mathrm{NaH}}_2{\mathrm{PO}}_2 \\ (\mathrm{sodium} \mathrm{hypophosphite}) \end{gathered}$$

Sodium hypophosphite is a salt of Phosphinic acid (Hypophosphorous acid).