The index for the Gold number is:

1. Protective power of lyophilic colloid.

2. Purity of gold.

3. Metallic gold.

4. Electroplated gold.

Silver iodide is used for producing artificial rain because AgI is:
1. Easy to spray at high altitudes.
2. Easy to synthesize.
3. Having crystal structure similar to ice.
4. Insoluble in water.

Which is an emulsion?

1. Boot polish                             

2. Lipstick

3. Shampoo                               

4. All of these

Egg albumin is:

1. reversible colloid

2. lyophilic colloid

3. protective colloid

4. all of these

The active species in Zeigler-Natta polymerisation of ethylene is:

1. AlCl₃

2. Et₃Al

3. H₂C=CH₂

4. Ti⁺³

The gas that is adsorbed strongly by charcoal is: 

1. CO₂                               

2. N₂

3. H₂                                 

4. NH₃

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^-

Milk contains a protein that is very good for health. The protein is:

1. caffeine

2. calciferol

3. keratin

4. casein

Emulsions of polyvinylacetate are used in:

1. polishes

2. latex paints

3. fire works

4. rayons