The correct statements pertaining to the adsorption of a gas on a solid surface are
(i) Adsorption is always exothermic
(ii) Physisorption may transform into chemisorption at high temperature
(iii) Physisorption increases with increasing temperature but chemisorotion decrease with increasing temperature
(iv) Chemisorption is more exothermic than physisoption, however, it is very slow due to higher energy of activation

Options

A. `(i),(ii),(iii),(iv)`
B. `(ii),(iii),(iv)`
C. `(i),(iii)`
D. `(ii),(iv)`

Answer

D

Explanation

Chemisorption of `H_(2)(g)` on glass surface is an endothermic process. Physisorption decreases with increasing temperature while chemisorption first increases then decreases with increasing temperature.