Question

Given ,$PC{l_3}$ on hydrolysis gives:
$(A){H_3}P{O_4}$
$(B){H_3}P{O_3}$
$(C)POC$
$(D){H_3}P{O_2}$

Answer 1

Hint: The chemical name of $PC{l_3}$ is Potassium trichloride. Hydrolysis is a chemical reaction in which the given compound reacts with the water molecules and its previous bonds get broken down. In this reaction news compounds are formed. There are some necessary conditions that a compound must fulfil to get hydrolysed which we will see in detail in solution.

Complete answer:
We know that hydrolysis reaction is a chemical reaction in which a compound reacts with water molecules and some new compounds are formed.
The conditions that are necessary for a compound to fulfil to get hydrolysed are:
- The central element should be electron deficient which should have low lying vacant orbitals. Sp, that it could the electrons from water molecules.
- There should not be any steric crowding.
So, in the case of $PC{l_3}$ , there is no steric crowding in the molecule and the phosphorus atom has low lying vacant orbitals present in it. In the hydrolysis reaction, the bonds between the phosphorus and chlorine break and also the bond in the water molecules break. And, hence, new bonds form as a result of hydrolysis.
Now, the hydrolysis reaction of Potassium trichloride $(PC{l_3})$ with water molecules is given as:
$PC{l_3} + 3{H_2}O \to {H_3}P{O_3} + 3HCl$
Therefore, the correct option is $(B){H_3}P{O_3}$ .

Note:
In this way we can write the hydrolysis reaction for any given inorganic compound. Similarly, in potassium pentachloride hydrolysis takes place as there is no steric crowding and low lying vacant orbitals are also present. In this case the products of hydrolysis of Potassium pentachloride are water, phosphoric acid and hydrochloric acid.