Which of the following phenomena is inversely proportional to adsorption?

Adsorption of a gas on a solid adsorbent follows the Freundlich adsorption isotherm. If $x$ is the mass of the gas adsorbed on mass '$m$' of the adsorbent at pressure $p$,then from the given graph,the extent of adsorption is proportional to:

Which one of the following equations represents the Freundlich adsorption isotherm?

For the adsorption of hydrogen on platinum,the activation energy is $30 \ kJ \ mol^{-1}$ and for the adsorption of hydrogen on nickel,the activation energy is $41.4 \ kJ \ mol^{-1}$. The logarithm of the ratio of the rates of chemisorption on equal areas of the metals at $300 \ K$ is $........$ (Nearest integer). Given: $\ln 10 = 2.3$,$R = 8.3 \ J \ K^{-1} \ mol^{-1}$.

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.

What is adsorption,adsorbate,adsorbent and desorption? Explain with appropriate examples.