Precipitation of solid from colloidal dispersion

Back to SURFACE CHEMISTRY

Your Progress

0 / 213 Answered

Correct

Incorrect

Accuracy

JEE • CHEMISTRY • SURFACE CHEMISTRY

Surface chemistry practice · Mixed difficulty

Choose an answer to check it, or open “View answer” to study the explanation. Sign in to save progress to your account.

Practice format and chapter quiz

These sets use single-correct-answer MCQs. They do not cover every JEE Main or JEE Advanced question format and are not full-length mock papers.

Take a chapter quiz →

Showing 121-150 of 213 questions

Preparing practice and saved progress…

121 Easy

121 of 213

Remembering +4 | -1

Cold cream is an example of

View answer and explanation

Correct option: C

Water in oil emulsion

Option C (Water in oil emulsion) is correct because cold cream is a mixture where water droplets are dispersed in an oil phase.

122 Medium

122 of 213

Understanding +4 | -1

Which one of the following characteristics is associated with adsorption

View answer and explanation

Correct option: D

\Delta G,\,\Delta H\,\mathrm{and}\,\Delta S

all are negative

Option D (

\Delta G,\,\Delta H\,\mathrm{and}\,\Delta S

all are negative) is correct because adsorption is an exothermic process (

\Delta H

is negative) that decreases randomness (

\Delta S

is negative), and it is spontaneous (

\Delta G

is negative).

123 Easy

123 of 213

Understanding +4 | -1

Which acts as negative catalyst?

View answer and explanation

Correct option: D

All of the above

Option D (All of the above) is correct because lead tetraethyl, glycerol, and ethanol can all act as negative catalysts in specific reactions.

124 Easy

124 of 213

Remembering +4 | -1

A substance which promotes the activity of a catalyst is known as :

View answer and explanation

Correct option: C

Promoter

Option C (Promoter) is correct because a promoter is a substance that enhances the activity of a catalyst.

125 Medium

125 of 213

Understanding +4 | -1

{AgNO}_3

added to excess of

{KI}

solution the colloidal sol obtained will be

View answer and explanation

Correct option: A

{AgI} / {I}^{-}

Option A (

{AgI} / {I}^{-}

) is correct because when

AgNO_3

is added to excess

KI

AgI

precipitates and adsorbs

I^-

ions, forming a negatively charged colloidal sol.

126 Easy

126 of 213

Remembering +4 | -1

Alloy is an example of

View answer and explanation

Correct option: C

Solid solution

Option C (Solid solution) is correct because an alloy is a homogeneous mixture of two or more metals (or a metal and a non-metal) in the solid state.

127 Medium

127 of 213

Understanding +4 | -1

Assertion: Barbers rub the face with alum stones after giving a shave.

Reason: Alum stones have antiseptic properties.

View answer and explanation

Correct option: C

Assertion is correct, but reason is wrong statement.

Option C is correct because barbers use alum to constrict blood vessels and stop bleeding after a shave, but alum's primary function isn't antiseptic.

128 Easy

128 of 213

Understanding +4 | -1

Whenever, gels are placed with their dispersed phase, they :

View answer and explanation

Correct option: D

All of the above

Option D is correct. Gels swell up, intake the dispersed phase, and develop imbibition when placed with their dispersed phase.

129 Easy

129 of 213

Remembering +4 | -1

Which one of the following methods is commonly used for destruction of colloid?

View answer and explanation

Correct option: D

By adding electrolyte

The correct answer is D (By adding electrolyte) because adding an electrolyte to a colloidal solution causes coagulation or precipitation of the colloid, leading to its destruction.

130 Medium

130 of 213

Understanding +4 | -1

When temperature is increased

View answer and explanation

Correct option: B

Extent of adsorption decreases in physisorption

Option B is correct because physisorption is an exothermic process, and according to Le Chatelier's principle, increasing the temperature will decrease the extent of adsorption.

131 Medium

131 of 213

Understanding +4 | -1

Adsorption is accompanied by

View answer and explanation

Correct option: D

All of the above

Option D (All of the above) is correct because adsorption is an exothermic process that decreases the randomness of the system, leading to a negative change in entropy and enthalpy.

132 Hard

132 of 213

Understanding +4 | -1

The Gold number of four protective colloids A, B, C and D are 0.03, 0.003, 10 and 30 resp. protective power of these colloids will be in the order

View answer and explanation

Correct option: A

B > A > C > D

Option A (B > A > C > D) is correct because the protective power of a colloid is inversely proportional to its Gold number.

133 Medium

133 of 213

Understanding +4 | -1

The magnitude of colligative properties in all colloidal dispersions is …..than solution :

View answer and explanation

Correct option: B

Lower

Option B (Lower) is correct because colloidal dispersions have fewer particles than true solutions, leading to smaller colligative properties.

134 Medium

134 of 213

Understanding +4 | -1

According to Freundlich adsorption isotherm, which of the following is correct?

View answer and explanation

Correct option: D

All the above are correct for different ranges of pressure

Option D (All the above are correct for different ranges of pressure) is correct because the Freundlich isotherm equation

\frac{x}{m} = kP^{1/n}

can simplify to

\frac{x}{m} \propto P^1

at low pressure and

\frac{x}{m} \propto P^0

at high pressure.

135 Easy

135 of 213

Understanding +4 | -1

Consider the following statements about Langmuir isotherm.

I. The free gas and adsorbed gas are in dynamic equilibrium.

II. All adsorption sites are equivalent.

III. The initially adsorbed layer can act as a substrate for further adsorption

IV. The ability of a molecule to get adsorbed at a given site is independent of the occupation of neighboring sites.

The correct statements are

View answer and explanation

Correct option: B

I, II and IV

Option A (C < N > O) is correct because nitrogen has a higher ionization energy than both carbon and oxygen due to its half-filled p orbitals.

Explore Other Chapters in CHEMISTRY

View All →

P-BLOCK ELEMENTS 736 MCQs Equilibrium 696 MCQs STRUCTURE OF ATOM 634 MCQs THERMODYNAMICS 536 MCQs CHEMICAL BONDING & MOLECULAR STRUCTURE 514 MCQs SOLUTIONS 480 MCQs

136 Medium

136 of 213

Understanding +4 | -1

Which of the following exhibits greater coagulation power towards a negative colloid?

View answer and explanation

Correct option: C

\mathrm{AlCl}_3

Option C (

\mathrm{AlCl}_3

) is correct because, according to the Hardy-Schulze rule, ions with higher charges have greater coagulating power, and

Al^{3+}

has the highest charge among the given options.

137 Easy

137 of 213

Understanding +4 | -1

Which of the following is the best protective colloid?

View answer and explanation

Correct option: A

Gelatin (Gold no.=0.005)

Option A (Gelatin) is correct because the protective power of a colloid is inversely proportional to its gold number, and Gelatin has the lowest gold number (0.005) among the given options.

138 Easy

138 of 213

Remembering +4 | -1

Catalyst only

View answer and explanation

Correct option: A

Decreases activation energy

Option A (Decreases activation energy) is correct because catalysts function by providing an alternative reaction pathway with a lower activation energy.

139 Easy

139 of 213

Remembering +4 | -1

An increase in the concentration of adsorbate at the surface relative to its concentration in bulk phase is called :

View answer and explanation

Correct option: A

Adsorption

Option A (Adsorption) is correct because it is the definition of an increase in adsorbate concentration at the surface compared to the bulk phase.

140 Medium

140 of 213

Understanding +4 | -1

\mathrm{As}_2 \mathrm{~S}_3

sol is most easily precipitated by which ion?

View answer and explanation

Correct option: A

\mathrm{Al}^{3 +}

Option A (

\mathrm{Al}^{3 +}

) is correct because according to the Hardy-Schulze rule, ions with higher charges are more effective at causing flocculation.

141 Medium

141 of 213

Remembering +4 | -1

Physical states of dispersed phase and dispersion medium in gel respectively are

View answer and explanation

Correct option: C

Liquid and solid

Option C (Liquid and solid) is correct because in a gel, the dispersed phase is a liquid and the dispersion medium is a solid.

142 Easy

142 of 213

Understanding +4 | -1

Removal of charge from colloids causes

View answer and explanation

Correct option: B

Coagulation

Option B (Coagulation) is correct because removal of charge from colloids leads to their instability and aggregation, resulting in coagulation.

143 Medium

143 of 213

Remembering +4 | -1

Butter is an example of

View answer and explanation

Correct option: D

Emulsion

Option D (Emulsion) is correct because butter is a mixture of two immiscible liquids (fat and water).

144 Easy

144 of 213

Remembering +4 | -1

Purple of cassius is

View answer and explanation

Correct option: A

Colloidal solution of Au

Option A (Colloidal solution of Au) is correct because Purple of Cassius is a colloidal solution of gold nanoparticles, often used to impart a red or purple color to glass and ceramics.

145 Medium

145 of 213

Understanding +4 | -1

On which of the following properties does the coagulating power of an ion depend ?

View answer and explanation

Correct option: C

Both magnitude and sign of the charge on the ion

Option C (Both magnitude and sign of the charge on the ion) is correct because the coagulating power of an ion depends on both its charge and its sign, as per the Hardy-Schulze rule.

146 Easy

146 of 213

Understanding +4 | -1

Which one of the following characteristics is associated with adsorption?

View answer and explanation

Correct option: B

\Delta \mathrm{G},\Delta \mathrm{H}\,\mathrm{and}\,\Delta \,\mathrm{S}

all are negative

Option B is correct because adsorption is an exothermic process (negative

\Delta H

), feasible (negative

\Delta G

), and involves a decrease in entropy (negative

\Delta S

147 Easy

147 of 213

Remembering +4 | -1

Which is kinetic phenomenon

View answer and explanation

Correct option: A

Brownian motion

Option A (Brownian motion) is correct because Brownian motion is a kinetic phenomenon resulting from the random movement of particles.

148 Medium

148 of 213

Remembering +4 | -1

Which among the following is used to purify colloidal solution?

View answer and explanation

Correct option: B

Dialysis

The correct answer is B (Dialysis) because dialysis is a method specifically used to purify colloidal solutions by removing impurities.

149 Easy

149 of 213

Remembering +4 | -1

Peptization denotes

View answer and explanation

Correct option: C

Breaking and dispersion into colloidal state

Option C (Breaking and dispersion into colloidal state) is correct because peptization is the process of converting a precipitate into a colloidal solution.

150 Medium

150 of 213

Understanding +4 | -1

The stablity of lyophillic colloids is due to which of the following?

View answer and explanation

Correct option: D

A layer of dispersion medium

Option D (A layer of dispersion medium) is correct because lyophilic colloids are stabilized by a solvation layer of the dispersion medium around the colloidal particles.

Revision notes and key takeaways

Review SURFACE CHEMISTRY in your textbook or class notes, then use this set to check your understanding.

Showing 121-150 of 213 questions

Your Progress

Surface chemistry practice · Mixed difficulty

Explore Other Chapters in CHEMISTRY

Continue Your Practice

Your practice