A plot of xm versus p for the adsorption of a gas on a solid gives a straight line with…

A plot of $\log\dfrac{x}{m}$ versus $\log p$ for the adsorption of a gas on a solid gives a straight line with slope equal to :
A $-\log K$
B $n$
C $\dfrac{1}{n}$
D $\log K$

Detailed Solution

Freundlich adsorption isotherm: $\dfrac{x}{m} = K\,p^{1/n}$ (with $n \gt 1$)
Taking logarithms on both sides: $\log\dfrac{x}{m} = \log K + \dfrac{1}{n}\log p$
This is of the form $y = c + mx$, the equation of a straight line.
So a plot of $\log\dfrac{x}{m}$ against $\log p$ is a straight line with slope $= \dfrac{1}{n}$
and intercept on the y-axis $= \log K$.
Hence the slope is equal to $\dfrac{1}{n}$.

Freundlich adsorption isotherm in past papers

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Practise Freundlich adsorption isotherm All 2 questions This chapter in 2006 AIPMT-PRE