Question

The mass of gas adsorbed, x, per unit mass of adsorbate, m, was measured at various pressures, p. A graph between $\log{x\over m}$ and $\log p$ gives a straight line with slope equal to 2 and the intercept equal to 0.4771. The value of $x\over m$ at a pressure of 4 atm is :

(Given log 3 = 0.4771)

Numerical Value Type

Comments

Surface chemistry, Adsorption, Freundlich adsorption isotherm

Answer 1

Ans. (48) [NTA answer is given 6]

Sol. $\left(x\over m\right)=k(P)^{1\over n}$

$\log\left(x\over m\right)=\log k+{1\over n}\log P$

Slop $={1\over n}=2$

So $n={1\over2}$

Intercept $\implies\log k=0.477$ So $k=$ Antilog $(0.477)=3$

So $\left(x\over m\right)=k(P)^{1\over n}$

$=3[4]^2=48$