Question

If $x$ gram of gas is adsorbed by m gram of adsorbent at pressure $P$, the plot of log $\frac{x}{m}$ versus $\log P$ is linear. The slope of the plot is: ($n$ and $k$ are constants and $n>1$)

• A. $\log k$
• B. $\frac{1}{n}$
• C. $2k$
• D. $n$

Answer 1

Answer: (B)

$\frac{1}{n}$

If x gram of gas is adsorbed by m gram of adsorbent at pressure P, the plot of log $\frac{x}{m}$ versus log P is linear. The slope of the plot is $\frac{1}{n}$ (n and k are constants and n $>1$)

According to Freundlich adsorption isotherm,
$\frac{x}{m}=k{P}^{\frac{1}{n}}$

$lo{g}_{10}\frac{x}{m}=\frac{1}{n}lo{g}_{10}P+lo{g}_{10}k$

This is the equation of straight line of type $y=mx+c$

$lo{g}_{10}k$ is the y intercept.