The charge on As₂S₃ sol is caused by the adsorption of:

1. H⁺                             

2. OH^-

3. ${\mathrm{O}}_2^{-}$                             

4. S^2-

Pd can adsorb 900 times its volume of hydrogen. This called:

1. Absorption

2. Adsorption

3. Occlusion

4. Both 2, and 3

The Brownian motion is due to:

(1)temperature fluctuations within the liquid phase

(2)attraction and repulsion between charges on the colloidal particles

(3)impact of the molecules of the dispersion medium on the colloidal particles

(4)convective currents

The phenomenon in which adsorption and absorption takes place simultaneously is called:

1. Desorption                       

2. Sorption

3. Both 1 and 2              

4. None of these

Cloud bursts are caused by?

Peptization is the process of?

1. Precipitating colloidal particles.

2. Purifying colloidal particles.

3. Dispersing the precipitate into a colloidal state.

4. None of the above.

Which acts as poison for Pd-charcoal in lindlar's catalyst ?

1. BaSO₄

2. Quiniline

3. Both 1. and 2.

4. None of these

Which is the electrolyte that is least effective in causing coagulation of +ve ferric hydroxide sol?

1. KBr

2. K₂SO₄

3. K₂CrO₄

4. K₃[Fe(CN)₆]

Platinized asbestos used as a catalyst in the manufacture of H₂SO₄ is an example of:

1. heterogeneous catalyst                   

2. auto-catalyst

3. homo-catalyst                                 

4. induced catalyst

In a reversible reaction, a catalyst:

1. increases the rate of the forward reaction only

2. increases the rate of the forward reaction to a greater extent than that of  the backward reaction

3. increases the rate of the forward reaction and decreases that of the backward reaction to the different extent

4. increases the rate of the forward and backward reactions equally