Fruendlich Isotherm

Q. The equation for Freundlich adsorption isotherm is

a) $\frac{x}{m}=k{p}^{\frac{1}{n}}$
b) $\left(lnx\right)=ln\left(mk\right)+\frac{1}{n}lnp$
c) $\frac{x}{m}=k{p}^{-n}$
d) Only a and b

1. a
2. b
3. c
4. d

Q.

Plot of log x/m against log P is a straight line inclined at an angle of ${45}^{\circ }$. When the pressure is 0.5 atm and Freundlich parameter. K is 100, the amount of the solute adsorbed per gram of adsorbent will be (log 5 = 0.6990)

1. 1 g
2. 2 g
3. 5 g
4. 3 g

Q.

For adsorption of gas on solid surface, the plots of log $\frac{x}{m}$ vs log P is linear with a slope equal to-

1. K
2. log K
3. Log C
4. 1/n(n being integer)

Q. What is the major drawback of Fruendlich isotherm?

1. Not applicable at high pressures
2. Not applicable to gases
3. Not applicable at moderate temperatures
4. Not applicable for solid surfaces

Q. A plot of log $\frac{x}{m}$ versus log P for the adsorption of a gas on a solid gives a straight line with slope equal to:

1. n
2. $\frac{1}{n}$
   
3. log K
4. - log K

Q. In an adsorption experiment, a graph between log$\frac{x}{m}$ versus logP was found to be linear with a slope of ${45}^o$. The intercept of the log(x/m) axis was found to be 0.3010. Calculate the amount of gas adsorbed per gram of charcoal under a pressure of 0.5 atm

1. 1
2. 2
3. 3
4. 4

Q. In Fruendlich Isotherm, the value of $\frac{1}{n}$ is

1. 1 in case of physisorption
2. 1 in case of chemisorption
3. 0 to 1 in all cases
4. Greater than 1 in all cases

Q. The graph plotted between log x/m (where x is the mass of adsorbate and m is the mass of the adsorbent) vs. log P was found to be a straight line. The slope and intercept of line leads to 1/n and log K values. Find the wrong statement:

1. The relation does not hold good at high pressures
2. The relation fails when chemical adsorption takes place
3. At a very low pressure, n = 1
4. On increasing the pressure, the value of n decreases

Q. The graph between $ln\left(\frac{x}{m}\right)$ and $ln\left(p\right)$ is a straight line inclined at an angle of ${45}^{\circ }$ where x is the mass of the solute absorbed and m is the mass of the absorbent while p is the pressure of the gas in atm. When the pressure is 0.5 atm and $ln\left(k\right)=0.693$ where k is the Freundlich constant, then what amount of solute will be adsorbed by 12 g of the adsorbent?

Q. In the adsorption of a gas on solid, Freundlich isotherm is obeyed. Thus, if the slope of the plot is zero, then the extent of adsorption is:

1. directly proportional to the pressure of gas
2. inversely proportional to the pressure of the gas
3. proportional to the square of the pressure of the gas
4. independent of the pressure of the gas