(a) Draw the structure of the following :
(i) `N_(2)O_(5)`
(ii) `XeOF_(4)`
(b) Explain the following observations :
(i) The electron gain enthalpy of sulphur atom has a greater negative value than that of oxygen atom.
(ii) Nitrogen does not form pentahalides.
(iii) In an aqueous solution, HI is a stronger acid than HCl.

Explanation

(a) (i) Structure of `N_(2)O_(5)`

(ii) structure of Xe `OF_(4)` :

(b) (i) The electron gain enthalpy of oxygen is least negative in this group , due to its small size.
(ii) Nitrogen does not form pentahalides due to the absence of d- orbitals in its valence shell.
(iii) The stregth of an acid depends upon its strengh . Since bond dissociation energy of HCl is greater than HI . Therefore , HI is stronger acid than HCl.