Question

Phosphine is obtained by the reaction when_________.

• A. white phosphorous is heated with $NaOH$
• B. $C{a}_3{P}_2$ reacts with water
• C. red phosphorus is heated with $NaOH$
• D. phosphorus is heated in current of hydrogen

Answer 1

Answer: (A), (B)

The correct options are
A white phosphorous is heated with $NaOH$
B $C{a}_3{P}_2$ reacts with water

When white phosphorus is reacted with phosphorus, the following reaction takes place,

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

Phospine Sodium hypophospine

Hence phosphine is formed.

When calcium phosphide $\left(C{a}_3{P}_2\right)$ reacts with water, the following reaction takes place

$C{a}_3{P}_2$ $+$ $6H_{2}O$ $⟶$ $3Ca(OH{)}_2$ $+$ $2P{H}_3$

Calcim hydroxide Phosphine

So phosphine is formed.

Hence, option A and B is correct.