In Freundlich adsorption isotherm at moderate pressure, the extent of adsorption $\left(\frac{x}{m}\right)$ is directly proportional to $\mathrm{P}^{\mathrm{x}}$. The value of x is :

JEE Main · 2021 · 25 Feb 2021 · Shift 1 · Surface Chemistry

In Freundlich adsorption isotherm at moderate pressure, the extent of adsorption

(\frac{x}{m})

is directly proportional to

P^{x}

. The value of x is :

Answer: (B)

The Freundlich isotherm writes the extent of adsorption as

\frac{x}{m} = k P^{1/ n}, n > 1

with

k

and

n

fixed for a given adsorbent and gas. At very low pressure the surface is almost bare and adsorption is proportional to

P

, at very high pressure the surface saturates and adsorption becomes independent of

P

; the moderate-pressure range lies between these, and the fractional exponent

\frac{1}{n}

is what describes it. The exponent is therefore

\frac{1}{n}

JEE Main · 2021 · 25 Feb 2021 · Shift 1 · Single correct option