The Langmuir adsorption isotherm is deduced using  the assumption: 

• the adsorption takes place in multilayers

• The adsorption sites are equivalent in their ability to adsorb the particles

• The adsorbed molecules interact with each other

• The adsorbed molecules interact with each other

A plot of log x/m versus log p for the adsorption of a gas on a solid gives a straight line with slope equal to:

• -log k

• n

• 1/n

• 1/n

On which of the following properties does the coagulating power of an ion depend?

• The magnitude of the charge on the ion alone

• Size of the ion alone

• The sign of the charge on the ion alone

• Both magnitude and sign of the charge on the ion

164.

Given van der Waals constant for NH₃, H₂, O₂ and CO₂ are respectively 4.17, 0.244, 1.36 and 3.59, which one of the following gases is most easily liquefied?

• NH₃

• H₂

• CO₂

• O₂

Which of the following is not applicable to the phenomenon of adsorption?

• ΔH> 0

• ΔG<0

• ΔS<0

• ΔH<0

On the basis of Langmuir adsorption isotherm the amount of gas adsorbed at very high pressure.

• Reaches a constant limiting value

• Goes on increasing with pressure

• Goes on decreasing with pressure

• First increasing and then decreasing with pressure

If x is amount of adsorbate and m is amount of adsorbent, which of the following relations is not related to adsorption process?

• $\frac{x}{m} = \mathrm{f}\left(T\right) \mathrm{at} \mathrm{constant} p$

• $p = \mathrm{f}\left(\mathrm{T}\right) \mathrm{at} \mathrm{constant} \left(\frac{x}{m}\right)$

• $\frac{x}{m} = p \times \mathrm{T}$

• $\frac{x}{m} = \mathrm{f}\left(\mathrm{p}\right) \mathrm{at} \mathrm{constant} \mathrm{T}$

Which of the following represents physical adsorption?

Which of the following curves is in accordance with Freundlich adsorption isotherm?

In the presence of a catalyst, the heat evolved or absorbed during the reaction

• increases

• decreases

• remains unchanged

• may increase or decrease