Question

Adsorption of a gas follows the Freundlich adsorption isotherm. 'x' is the mass of the gas adsorbed on mass 'm' of the adsorbent. The plot of $log\frac{x}{m}$ versus $logp$ is shown in the graph given below, $\frac{x}{m}$ is proportional to:

• A. $p^{\frac{2}{3}}$
• B. $p^2$
• C. $p^3$
• D. $p^{\frac{3}{2}}$

Answer 1

The correct option is A $p^{\frac{2}{3}}$

According to Freundlich adsorption isotherm,
$\frac{x}{m}=K{p}^{\frac{1}{n}}$
Taking log,
$log\frac{x}{m}=logK+\frac{1}{n}logp$
Slope $\frac{1}{n}=\frac{2}{3}$ [From the graph]
So, $\frac{x}{m}\propto p^{\frac{2}{3}}$