Identify the gas adsorbed by solid to the largest extent at their respective critical temperature.

Match the Xenon compounds in Column-1 with its structure in Column-II.

Column – I	Column – II
(a) $\text{XeF}_4$	(i) pyramidal
(b) $\text{XeF}_6$	(ii) square planar
(c) $\text{XeOF}_4$	(iii) distorted octahedral
(d) $\text{XeO}_3$	(iv) square pyramidal

Which of the following lanthanoids is radioactive?

Which transition series includes elements Co and Mo respectively?