5. Co-ordination chemistry — Chemistry STD 12 Science — Question

Statement $I$: The boiling point of hydrides of Group $16$ elements follow the order

$\mathrm{H}_2 \mathrm{O}>\mathrm{H}_2 \mathrm{Te}>\mathrm{H}_2 \mathrm{Se}>\mathrm{H}_2 \mathrm{~S}$.

Statement $II$: On the basis of molecular mass, $\mathrm{H}_2 \mathrm{O}$ is expected to have lower boiling point than the othe members of the group but due to the presence of extensive $\mathrm{H}$-bonding in $\mathrm{H}_2 \mathrm{O}$, it has higher boiling point.

In the light of the above statements, choose the correct answer from the options given below:

$ {\left[\mathrm{Ag}\left(\mathrm{NH}_3\right)\right]^{+}+\mathrm{NH}_3 \rightleftharpoons\left[\mathrm{Ag}\left(\mathrm{NH}_3\right)_2\right]^{+} ; \mathrm{k}_2=1.7 \times 10^{-3}}$

then the formation constant of $\left[\mathrm{Ag}\left(\mathrm{NH}_3\right)_2\right]^{+}$is