In Freundlich adsorption isotherm, slope of AB line is :
- $\log n$ with $( n >1)$
- $n$ with $( n , 0.1$ to 0.5$)$
- $\log \frac{1}{n}$ with $(n<1)$
- $\frac{1}{ n }$ with $\left(\frac{1}{ n }=0\right.$ to $\left.1\right)$
The Correct Option is D
Solution and Explanation
The Freundlich adsorption isotherm is a scientific formula that helps describe how solutes interact with surfaces. It is typically written as:
\(x/m = k \cdot C^{\frac{1}{n}}\)
where:
- \(x/m\) is the amount of adsorbate per unit mass of adsorbent.
- \(C\) is the concentration of the solute in the solution.
- \(k\) and \({1}/{n}\) are constants.
To align with experimental data, we often convert this into a logarithmic form:
\(\log\left(\frac{x}{m}\right) = \log(k) + \frac{1}{n} \log(C)\)
In this equation, \(\log(k)\) is the intercept and \(\frac{1}{n}\) is the slope of the line obtained in a plot of \(\log(x/m)\) versus \(\log(C)\). In the options given, the correct answer relates to this slope.
The correct answer is:
- \(\frac{1}{n}\) with \(\left(\frac{1}{ n }=0\right.\) to \(\left.1\right)\)
This is because the slope in the logarithmic form of the Freundlich isotherm is exactly \(\frac{1}{n}\), and \(\frac{1}{n}\) typically ranges between 0 and 1. This reflects the effectiveness of adsorption — if \(n > 1\), it means that adsorption is favorable across a wide range of concentrations.
Top Questions on Adsorption
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Concepts Used:
Adsorption
Heinrich Kayser, the German physicist was the first to coin the term adsorption. Adsorption can be explained as a surface phenomenon where particles remain attached on the top of a material. Generally, it comprises the molecules, atoms, liquid, solid in a dissolved stage, even the ions of a gas that are attached to the surface. Much to our surprise, the consequence of surface energy i.e. adsorption is present in biological, physical, chemical, and natural systems and are used in many industrial applications.
