If the concentration of reactants is increased by $x$,then the equilibrium constant $K$ becomes:

For the reaction ${H_2} + {I_2} \rightleftharpoons 2HI$ at $721 \ K$,the value of the equilibrium constant is $50$. If $0.5 \ mol$ of each of ${H_2}$ and ${I_2}$ are added to the system,the value of the equilibrium constant will be .............

Explain the dynamic nature of chemical equilibrium with a suitable reaction example.

When pure ammonia is placed in a vessel at constant temperature,at equilibrium:

In the chemical reaction ${N_2} + 3{H_2} \rightleftharpoons 2N{H_3}$,at the equilibrium point ...............

$A$ liquid is in equilibrium with its vapour in a sealed container at a fixed temperature. The volume of the container is suddenly increased.
$(a)$ What is the initial effect of the change on vapour pressure?
$(b)$ How do rates of evaporation and condensation change initially?
$(c)$ What happens when equilibrium is restored finally and what will be the final vapour pressure?