$Co$ and $Ni$ have lesser radii than $Cu$ and $Zn$. Also in $Co$ the number of unpaired electrons are more.
$\mathrm{Na}_{2} \mathrm{S}$ is ionic, soluble in water, has highest solubility. $\mathrm{K}_{\mathrm{sp}}$ of $\mathrm{ZnS}$ is higher than $CuS$, therefore, solubility is higher.
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Statement $I$ : Nickel is being used as the catalyst for producing syn gas and edible fats.
Statement $II$ : Silicon forms both electron rich and electron deficient hydrides.
In the light of the above statements, choose the most appropriate answer from the options given below:
$kJ\,mol ^{-1}$ (Nearest integer)
Given : $\Delta_{ dis } H _{ Cl _{2(g)}}^{\circ}=240\,kJ\,mol ^{-1}$.
$\Delta_{ eg } H _{ Cl _{(g)}}^{\circ}=-350\,kJ\,mol ^{-1}$,
$\Delta_{ hyd } H _{ Cl i _{( j )}^{\circ}}^{\circ}=-380\,kJ\,mol ^{-1}$
