The following two reactions:
i. `PCl_(5)(g) hArr PCl_(3)(g)+Cl_(2)(g)`
(ii) `COCl_(2)(g) hArr CO(g)+Cl_(2)(g)`
are simultaneously in equilibrium in a container at constant volume. A few moles of `CO(g)` are later introduced into the vessel. After some time, the new equilibrium concentration of

Options

A. `PCl_(5)` will increases
B. `PCl_(5)` will remain unaffected
C. `Cl_(2)` will increases
D. `PCl_(5)` will decreases

Answer

B

Explanation

Given : (i) ` H_(2) S hArr HS^(-) + H^(+),`
`K_(a_(1)) = 1.0 xx 10^(-7)`
(ii) `HS^(-) hArr S^(2-) + H^(+), K_(a_(2))= 1.2 xx 10^(-13)`
For the reaction , ` H_(2)S hArr 2 H^(+) + S^(2-)`
(obtained by adding (i) and (ii) )
`K_(a) =