Which oxide is used as a catalyst in the contact process?

Assertion : There is a large difference between the melting and boiling points of $O$ and $S$.
Reason : It can be explained on the basis of their atomicity in $O_2$ and $S_8$ molecules.

The thermal stability of the hydrides of group-$16$ elements follows the order:

Assertion : Dinegative anion of oxygen $(O^{2-})$ is quite common but dinegative anion of sulphur $(S^{2-})$ is less common.
Reason : Covalency of oxygen is two.

Why is a Tyndall box used in the manufacture of sulfuric acid by the contact process?

Which of the following sets of atomic numbers corresponds to elements of group $16$?