Which statements among the following are correct?
$(i)$ Freundlich isotherm fails at high pressure of the gas.
$(ii)$ $\Delta H < 0$ for both physical and chemical adsorption.
$(iii)$ Physical adsorption is non-selective.
$(iv)$ Chemical adsorption is reversible,whereas physical adsorption is irreversible.

$50 \ mL$ of $1 \ M$ oxalic acid is shaken with $0.5 \ g$ of wood charcoal. The final concentration of the solution after adsorption is $0.5 \ M$. The amount of oxalic acid adsorbed per $g$ of charcoal is ....... $g$.

Which of the following gases is adsorbed to maximum extent?

Assertion : The enthalpy of physisorption is greater than chemisorption.
Reason : Molecules of adsorbate and adsorbent are held by van der Waal's forces in physisorption and by chemical bonds in chemisorption.

In the figure,a straight line is given for the Freundlich Adsorption isotherm equation $(y = mx + c)$,where the equation is $y = 0.3x + 0.7033$. The values of $\frac{1}{n}$ and $\log K$ are respectively:

The correct statement$(s)$ pertaining to the adsorption of a gas on a solid surface is (are):
$(A)$ Adsorption is always exothermic.
$(B)$ Physisorption may transform into chemisorption at high temperature.
$(C)$ Physisorption increases with increasing temperature but chemisorption decreases with increasing temperature.
$(D)$ Chemisorption is more exothermic than physisorption,however it is very slow due to higher energy of activation.