Milk can be preserved by adding a few drops of?

1. Formic acid solution             

2. Formaldehyde solution

3. Acetic acid solution             

4. Acetaldehyde solution

When a catalyst is added to a system the:

1. equilibrium concentrations are increased

2. equilibrium concentrations are unchanged

3. the rate of forward reaction is increased and that of backward reaction is decreases

4. value of the equilibrium constant is decreased

Clouds, mist, fog and aerosols are colloidal solution of:

1. solid in a gas

2. gas in a solid

3. liquid in a gas

4. gas in a liquid

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