A small amount of phosphoric acid can be used to prevent H₂O₂ decomposition. This an example of?

1. Neutralization                             

2. Negative catalysis

3. Positive catalysis                         

4. Catalytic poisoning

Which ion is adsorbed when a diluted aqueous solution of AgNO₃ (excess) is added to KI solution, resulting in formation of positively charged sol particles of AgI?

1. K⁺

2. Ag⁺

3. I^-

4. NO₃^-

What is the simultaneous outcome of internal liquid from gels called?

1. Synerisis                         

2. Thixotropy

3. Swelling                           

4. None of the above

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

1. H⁺                             

2. OH^-

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

4. S^2-

Given below are three process:

a. Emulsification

b. Adsorption

c. Absorption

The process of froth flotation and chromatography is based on:
1. a & b
2. b & c
3. a & c
4. None of the above

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 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]

In adding 1 mL of solution of 10 % NaCl to 10 mL of gold solution in the presence of 0.25 g of starch, the coagulation is just prevented. Starch has a gold number equal to:

1. 0.25                     

2. 2.5

3. 250                     

4. 0.025

What is a solution that isn't a lyophilic colloid?

1. Milk

2. Gum

3. Fog

4. Blood