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

Gold number is the index for:

(a)protective power of lyophilic colloid

(b)purity of gold

(c)metallic gold

(d)electroplated gold

Which is an emulsion?

(1) Boot polish                             

(2) Lipstic

(3) Shampoo                               

(4) All of these

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

(a) caffeine

(b) calciferol

(c) keratin

(d) casein

The charge on As₂S₃ sol is due to the adsorption of:

(1) H⁺                             

(2) OH^-

(3) ${\mathrm{O}}_2^{-}$                             

(4) S^2-

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

(a) BaSO₄

(b) Quiniline

(c) Both (a) and (b)

(d) None of these

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

Gas masks containing activated charcoal to remove poisonous gases from atmosphere acts on the principle of:

(1) Adsorption

(2) Absorption

(3) Sorption

(4) All of these

Tanning of leather is:

(1) Colouring of leather by chemicals

(2) Drying process to make the leather hard

(3) Polishing of leather to make it look attractive

(4) Coagulative hardening of the leather by chemicals

When sulphur sol is evaporated solid sulphur is left. On mixing with water no colloidal sol is formed. Sulphur sol is: 

(a)hydrophilic

(b)hydrophobic

(c)reversible

(d)lyophilic