Provide information about the allotropes of phosphorus.

(N/A) Phosphorus is found in many allotropic forms,among which white,red,and black phosphorus are important.
$(a)$ White Phosphorus: It is obtained by industrial synthesis.
It is a translucent white waxy solid.
It is poisonous,insoluble in water but soluble in carbon disulfide,and glows in the dark (chemiluminescence).
It dissolves in boiling $NaOH$ solution in an inert atmosphere to give $PH_3$.
$P_4 + 3NaOH + 3H_2O \rightarrow PH_3 + 3NaH_2PO_2$
It consists of discrete tetrahedral $P_4$ molecules as shown in the figure.
$(b)$ Red Phosphorus: It is obtained by heating white phosphorus at $573 \ K$ in an inert atmosphere for several days.
Red phosphorus has an iron-grey lustre.
It is odourless,non-poisonous,and insoluble in water as well as in carbon disulfide.
It is much less reactive than white phosphorus and does not glow in the dark. It is polymeric.
As shown in the figure,it consists of chains of $P_4$ tetrahedral units linked together.