Question 1

The charge on colloidal particies is due to

Accepted Answer

The colloidal particles have a tendency to preferentially adsorb a particular type of ions form the solution. This preferential adsorption of a particular type of ions imparts a particular type of charge to colloidal narticles.

Question 2

Point out the false statement :

Accepted Answer

Colloid of liquid in liquid is called emulsion. Colloid of liquid in solid is gel.

Question 3

Which of the following method is used for coagulation of the sol?

Accepted Answer

No Solution Available

Question 4

Adsorption of a gas follows Freundlich adsorption isotherm. x is the mass of the gas adsorbed on mass m of the adsorbent. The plot of x m versus p is shown in the given graph. x m is proportional to :

Accepted Answer

According to Freundlich adsorption isotherm x m p^ 1 n , x m =k p^ 1 n Slope = 2 3 x m = k+ 1 n p Slope = 1 n = 2 3 x m p^ 2 3

Question 5

Methylene blue, from its aqueous solution, is adsorbed on activated charcoal at 25^ C . For this process, which ofthe following statement is correct?

Accepted Answer

The adsorption of methylene blue on activated charcoal is an example of physiosorption which is exothermic, multilayer and does not have energy barrier.

Surface Chemistry — Previous Year Questions & Solutions