Question

Assertion :The numerical value of $\frac{1}{n}$ in Freundlich adsorption isotherm, $\frac{x}{m}=K(P{)}^{1/n}$ at saturation pressure is zero. Reason: At saturation pressure, the amount adsorbed per unit volume does not change with increase in pressure.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
• C. Assertion is correct but Reason is incorrect.
• D. Assertion is incorrect but Reason is correct.

Answer 1

The correct option is B Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.

The numerical value of $1/n$ in Freundlich adsorption isotherm $\frac{x}{m}=K(P{)}^{1/n}$ at saturation pressure is zero.
At high pressure, the expression for Freundlich adsorption isotherm becomes $\frac{x}{m}=K(P{)}^o\therefore \frac{1}{n}=0$
At saturation pressure, the amount adsorbed per unit volume does not change with an increase in pressure. This is because the entire surface of the adsorbent is covered and no further adsorption is possible.
Thus, both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.