Question

Which of the following represent the Freundlich adsorption isotherms?




Choose the correct answer from the options given below: 

• A. A, B only
• B. B, C, D only
• C. A, B, D only
• D. A, C, D only

Answer 1

The Correct Option is C

The problem is asking which graphs represent Freundlich adsorption isotherms. To solve this, we need to understand the Freundlich adsorption isotherm equation.

The Freundlich adsorption isotherm is represented by the equation:

\[\frac{x}{m} = k \cdot p^{1/n}\]

where:

• x is the mass of adsorbate.
• m is the mass of adsorbent.
• p is the pressure of the adsorbate.
• k and n are constants specific to the system.

In a log-log graph, the Freundlich isotherm can be written as:

\[\log \left( \frac{x}{m} \right) = \log k + \frac{1}{n} \log p\]

This shows a linear relationship between \log \left( \frac{x}{m} \right) and \log p, indicative of a straight line with slope \frac{1}{n}.

Let's analyze each graph:

Graph A: This shows \frac{x}{m} vs p, which can represent the Freundlich isotherm.

Graph B: This shows \log \left( \frac{x}{m} \right) vs \log p, which fits perfectly with the linear form of Freundlich isotherm.

Graph C: This shows \frac{x}{m} vs c (concentration), not directly related to the Freundlich equation.

Graph D: This illustrates \frac{x}{m} vs p^{1/n}, which is another way to show the Freundlich isotherm.

Thus, the correct graphs that represent the Freundlich adsorption isotherms are:

• A
• B
• D

Therefore, the correct answer is: A, B, D only.