Chemistry 12 Chapter 5 Exemplar Solutions Surface Chemistry Part 2

Doorsteptutor material for NSTSE is prepared by world's top subject experts: Get full length tests using official NTA interface: all topics with exact weightage, real exam experience, detailed analytics, comparison and rankings, & questions with full solutions.

II. Multiple Choice Questions (Type-II)

Note: In the following questions two or more options may be correct

Question 26:

Which of the following options are correct?

(i) Micelle formation by soap in aqueous solution is possible at all temperatures.

(ii) Micelle formation by soap in aqueous solution occurs above a particular concentration.

(iii) On dilution of soap solution micelles may revert to individual ions.

(iv) Soap solution behaves as a normal strong electrolyte at all concentrations.

Answer: (ii), (iii)

Question 27:

Which of the following statements are correct about solid catalyst?

(i) Same reactants may give different product by using different catalysts.

(ii) Catalyst does not change of reaction.

(iii) Catalyst is required in large quantities to catalyse reactions.

(iv) Catalytic activity of a solid catalyst does not depend upon the strength of chemisorption.

Answer: (i), (ii)

Question 28:

Freundlich adsorption isotherm is given by the expression which of the following conclusions can be drawn from this expression.

(i) When , the adsorption is independent of pressure.

(ii) When the adsorption is directly proportional to pressure.

(iii) When vs graph is a line parallel to axis.

(iv) When , plot of vs is a curve.

Answer: (i), (iii)

Question 29:

gas is adsorbed on activated charcoal to a very little extent in comparison to easily liquefiable gases due to ____________.

(i) Very strong van der Waal’s interaction.

(ii) Very weak van der Waals forces.

(iii) Very low critical temperature.

(iv) Very high critical temperature.

Answer: (ii), (iii)

Question 30:

Which of the following statements are correct?

(i) Mixing two oppositely charged sols neutralises their charges and stabilises the colloid.

(ii) Presence of equal and similar charges on colloidal particles provides stability to the colloids.

(iii) Any amount of dispersed liquid can be added to emulsion without destabilizing it.

(iv) Brownian movement stabilises sols.

Answer: (ii), (iv)

Question 31:

An emulsion cannot be broken by __________ and ___________.

(i) Heating

(ii) Adding more amount of dispersion medium

(iii) Freezing

(iv) Adding emulsifying agent

Answer: (ii), (iv)

Question 32:

Which of the following substances will precipitate the negatively charged emulsions?

(i)

(ii) Glucose

(iii) Urea

(iv)

Answer: (i), (iv)

Question 33:

Which of the following colloids cannot be coagulated easily?

(i) Lyophobic colloids.

(ii) Irreversible colloids.

(iii) Reversible colloids.

(iv) Lyophilic colloids.

Answer: (iii), (iv)

Question 34:

What happens when a lyophilic sol is added to a lyophobic sol?

(i) Lyophobic sol is protected.

(ii) Lyophilic sol is protected.

(iii) Film of lyophilic sol is formed over lyophobic sol.

(iv) Film of lyophobic sol is formed over lyophilic sol.

Answer: (i), (iii)

Question 35:

Which phenomenon occurs when an electric field is applied to a colloidal solution and electrophoresis is prevented?

(i) Reverse osmosis takes place.

(ii) Electroosmosis takes place.

(iii) Dispersion medium begins to move.

(iv) Dispersion medium becomes stationary.

Answer: (ii), (iii)

Question 36:

In a reaction, catalyst changes ____________.

(i) Physically

(ii) Qualitatively

(iii) Chemically

(iv) Quantitatively

Answer: (i), (ii)

Question 37:

Which of the following phenomenon occurs when a chalk stick is dipped in ink?

(i) Adsorption of coloured substance

(ii) Adsorption of solvent

(iii) Absorption and adsorption both of solvent

(iv) Absorption of solvent

Answer: (i), (iv)