Select the correct statements:

$\text{ (1) On heating molten Ag, it absorbs oxygen which is again released }$$\text{ on cooling is called "spitting of Ag" and }$$\mathrm{is}\mathrm{prevented} \mathrm{by}$

$\mathrm{charcoal}$

(2) Cr $\Rightarrow$ 3d⁵ 4s¹ (6 unpaired e^-,s), $\mathrm{Fe}\Rightarrow 3{\mathrm{d}}^{6}4{\mathrm{s}}^2\left(4\text{ unpaired }{\mathrm{e}}^{-\mathrm{r}}\mathrm{s}\right)$
$\left.\mathrm{Zn}\Rightarrow 3{\mathrm{d}}^{10}4{\mathrm{s}}^2\text{ (no unpaired }{\mathrm{e}}^{-5}\mathrm{s}\right)$
(3) Fact
(4) M. Pt. and B. Pt., are low.
In Zn, Cd and Hg, (n - 1)d orbitals are filled to their maximum capacity. These e^-'s do not take part in bonding. Thus, metallic bonding is weak and hence low M. Pt. and B. Pt.