The empirical Freundlich adsorption isotherm is given as . When this equation is tested at exceeding — Surface Chemistry Chemistry Question

💡 Solution & Explanation

The Freundlich isotherm empirically models adsorption well at moderate pressures. However, experimentally, at very high pressures, the solid surface becomes completely saturated with adsorbate (forming a monolayer), meaning further pressure increases do not increase adsorption. Therefore, $\frac{x}{m}$ becomes a constant, which implies $\frac{x}{m} \propto p^0$. Thus, $1/n$ mathematically approaches 0.