How many questions from Surface Chemistry appear in JEE?

Surface Chemistry has appeared in 98 of the last 186 JEE Main and JEE Advanced papers — about 53% of them — contributing 102 questions in total across those papers.

Is Surface Chemistry an important chapter for JEE?

Judged by how often it is actually tested, it appears in roughly 53% of papers. Chapters above about 50% are effectively guaranteed to show up every session, so they repay thorough preparation; lower-frequency chapters are better treated as targeted revision.

Where do these Surface Chemistry questions come from?

Every question is from an official JEE Main or JEE Advanced paper, transcribed from the original paper and tagged to this chapter. Answers follow the official answer key.

Surface Chemistry JEE Previous Year Questions with Answers

Q1·ChemistryNumericalJEE Advanced 2026

At a given temperature, 0.45 g of acetic acid in 50 mL of water is shaken with 1.0 g of charcoal and the pH of the resulting solution is 3.0. Assume, the adsorption of acetic acid from the aqueous solution by charcoal follows Freundlich isotherm,

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

If the plot of

\log_{10}(x/m)

against

\log_{10} C

gives a straight line with slope 1, the value of

k

in L

mol^{-1}

is ____. Given: The molar mass of acetic acid is 60 g

mol^{-1}

. The acid dissociation constant of acetic acid is

1.0 \times 10^{-5}

at the given temperature.

x

is the mass (in grams) of acetic acid adsorbed.

m

is the mass (in grams) of charcoal.

C

is the equilibrium concentration of acetic acid in the solution after the adsorption is complete.

k

and

n

are constants for acetic acid

-

charcoal system at the given temperature.

Q2·ChemistryNumericalJEE Advanced 2025

Adsorption of phenol from its aqueous solution on to fly ash obeys Freundlich isotherm. At a given temperature, from 10 mg g

^{-1}

and 16 mg g

^{-1}

aqueous phenol solutions, the concentrations of adsorbed phenol are measured to be 4 mg g

^{-1}

and 10 mg g

^{-1}

, respectively. At this temperature, the concentration (in mg g

^{-1}

) of adsorbed phenol from 20 mg g

^{-1}

aqueous solution of phenol will be ________. Use: log

_{10}

2 = 0.3

Q3·ChemistryNumericalJEE Advanced 2024

To form a complete monolayer of acetic acid on 1g of charcoal, 100 mL of 0.5 M acetic acid was used. Some of the acetic acid remained unadsorbed. To neutralize the unadsorbed acetic acid, 40 mL of 1 M NaOH solution was required. If each molecule of acetic acid occupies P

\times 10^{-23}

m

^{2}

surface area on charcoal, the value of P is ______. [Use given data : Surface area of charcoal =

1.5\times 10^{2}

m

^{2}

g

^{-1}

; Avogadro's number (

N_A

) =

6.0\times 10^{23}

mol

^{-1}

]

Q4·ChemistrySingle correctJEE Advanced 2023

Consider the following statements related to colloids. (I) Lyophobic colloids are not formed by simple mixing of dispersed phase and dispersion medium. (II) For emulsions, both the dispersed phase and the dispersion medium are liquid. (III) Micelles are produced by dissolving a surfactant in any solvent at any temperature. (IV) Tyndall effect can be observed from a colloidal solution with dispersed phase having the same refractive index as that of the dispersion medium. The option with the correct set of statements is

(A)(I) and (II)
(B)(II) and (III)
(C)(III) and (IV)
(D)(II) and (IV)

Q5·ChemistryNumericalJEE Main 2023

20 mL of 0.5 M NaCl is required to coagulate 200 mL of

As_2S_3

solution in 2 hours. The coagulating value of NaCl is _______

Q6·ChemistrySingle correctJEE Main 2023

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: The diameter of colloidal particles in solution should not be much smaller than wavelength of light to show Tyndall effect. Reason R: The light scatters in all directions when the size of particles is large enough. In the light of the above statements, choose the correct answer from the options given below:

(A)A is true but R is false
(B)A is false but R is true
(C)Both A and R are correct and R is the correct explanation of A
(D)Both A and R are correct but R is NOT the correct explanation of A

Q7·ChemistrySingle correctJEE Main 2023

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

(A)Lyophilic sol is dispersed in lyophobic sol
(B)Film of lyophilic sol is formed over lyophobic sol
(C)Lyophobic sol is coagulated
(D)Film of lyophobic sol is formed over lyophilic sol

Q8·ChemistrySingle correctJEE Main 2023

Four gases A, B, C and D have critical temperatures 5.3, 33.2, 126.0 and 154.3K respectively. For their adsorption on fixed amount of charcoal, the correct order is:

(A)C > B > D > A
(B)C > D > B > A
(C)D > C > A > B
(D)D > C > B > A

Q9·ChemistrySingle correctJEE Main 2023

25 mL of silver nitrate solution (1 M) is added dropwise to 25 mL of potassium iodide (1.05 M) solution. The ion(s) present in very small quantity in the solution is/are

(A) $NO_3^-$ only
(B) $K^+$ only
(C) $Ag^+$ and $I^-$ both
(D) $I^-$ only

Q10·ChemistryNumericalJEE Main 2023

The number of correct statements about the modern adsorption theory of heterogeneous catalysis from the following is ____. A. The catalyst is diffused over the surface of reactants. B. Reactants are adsorbed on the surface of the catalyst. C. Occurrence of chemical reaction on the catalyst's surface through formation of an intermediate. D. It is a combination of intermediate compound formation theory and the old adsorption theory. E. It explains the action of the catalyst as well as those of catalytic promoters and poisons.

Q11·ChemistrySingle correctJEE Main 2023

Ferric chloride is applied to stop bleeding because:

(A) $\text{Cl}^-$ ions cause coagulation of blood.
(B)Blood absorbs $\text{FeCl}_3$ and forms a complex.
(C) $\text{Fe}^{3+}$ ions coagulate blood which is a negatively charged sol.
(D) $\text{FeCl}_3$ reacts with the constituents of blood which is a positively charged sol.

Q12·ChemistrySingle correctJEE Main 2023

The enthalpy change for the adsorption process and micelle formation respectively are

(A) $\Delta H_{ads}<0$ and $\Delta H_{mic}>0$
(B) $\Delta H_{ads}>0$ and $\Delta H_{mic}<0$
(C) $\Delta H_{ads}<0$ and $\Delta H_{mic}<0$
(D) $\Delta H_{ads}>0$ and $\Delta H_{mic}>0$

Q13·ChemistrySingle correctJEE Main 2023

Which of the following represent the Freundlich adsorption isotherms? Choose the correct answer from the options given below:

(A)B, C, D only
(B)A, B, D only
(C)A, B only
(D)A, C, D only

Q14·ChemistryNumericalJEE Main 2023

Coagulating values of the electrolytes

AlCl_3

and

NaCl

for

As_2S_3

are 0.09 and 50.04 respectively. The coagulating power of

AlCl_3

is x times the coagulating power of

NaCl

. The value of x is ____.

Q15·ChemistryNumericalJEE Main 2023

For the adsorption of hydrogen on platinum, the activation energy is

30\,kJ\,mol^{-1}

and for the adsorption of hydrogen on nickel, the activation energy is

41.4\,kJ\,mol^{-1}

. The logarithm of the ratio of the rates of chemisorption on equal areas of the metals at

300\,K

is _____. (Nearest integer) Given:

\ln 10=2.3,\,R=8.3\,J\,K^{-1}\,mol^{-1}

.

Q16·ChemistryNumericalJEE Main 2023

The number of colloidal systems from the following, which will have 'liquid' as the dispersion medium, is ____. Gem stones, paints, smoke, cheese, milk, hair cream, insecticide sprays, froth, soap lather.

Q17·ChemistrySingle correctJEE Main 2023

A straight line is given for Freundlich Adsorption (

y=3x+2.505

). The value of

\dfrac1n

and

\log K

are respectively.

(A) $0.3$ and $0.7033$
(B) $0.3$ and $\log 2.505$
(C) $3$ and $0.7033$
(D) $3$ and $2.505$

Q18·ChemistrySingle correctJEE Main 2023

Match List I (adsorption-related terms) with List II. Choose the correct answer from the options given below:

List I	List II
A.Physisorption	I.Single Layer Adsorption
B.Chemisorption	II.20–40 kJ mol $^{-1}$
C. $N_2(g)+3H_2(g)\xrightarrow{Fe(s)}2NH_3(g)$	III.Chromatography
D.Analytical Application of Adsorption	IV.Heterogeneous catalysis

(A)A-II, B-I, C-IV, D-III
(B)A-IV, B-II, C-III, D-I
(C)A-II, B-III, C-I, D-IV
(D)A-III, B-IV, C-I, D-II

Q19·ChemistrySingle correctJEE Main 2023

Adding surfactants in non polar solvent, the micelles structure will look like

(A)a
(B)d
(C)b
(D)c

Q20·ChemistryNumericalJEE Main 2023

The graph of

\log\dfrac{x}{m}

vs

\log p

for an adsorption process is a straight line inclined at an angle of

45^{\circ}

with intercept equal to 0.6020. The mass of gas adsorbed per unit mass of adsorbent at a pressure of 0.4 atm is _______

\times10^{-1}

(nearest integer). (Given:

\log 2=0.3010

)

Q21·ChemistrySingle correctJEE Main 2023

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): In expensive scientific instruments, silica gel is kept in watch-glasses or in semipermeable membrane bags. Reason (R): Silica gel adsorbs moisture from air via adsorption, thus protects the instrument from water corrosion (rusting) and/or prevents malfunctioning. In the light of the above statements, choose the correct answer from the options given below:

(A)Both (A) and (R) are true but (R) is not the correct explanation of (A)
(B)(A) is false but (R) is true
(C)Both (A) and (R) are true and (R) is the correct explanation of (A)
(D)(A) is true but (R) is false

Q22·ChemistrySingle correctJEE Main 2023

Which of the following salt solution would coagulate the colloid solution formed when FeCl

_3

is added to NaOH solution, at the fastest rate?

(A)10 mL of 0.1 mol dm $^{-3}$ Na $_2$ SO $_4$
(B)10 mL of 0.2 mol dm $^{-3}$ AlCl $_3$
(C)10 mL of 0.1 mol dm $^{-3}$ Ca $_3$ (PO $_4$ ) $_2$
(D)10 mL of 0.15 mol dm $^{-3}$ CaCl $_2$

Q23·ChemistrySingle correctJEE Main 2023

Match List I and List II. Choose the correct answer from the options given below:

List I	List II
A.Osmosis	I.Solvent molecules pass through semi permeable membrane towards solvent side.
B.Reverse osmosis	II.Movement of charged colloidal particles under the influence of applied electric potential towards oppositely charged electrodes.
C.Electro osmosis	III.Solvent molecules pass through semi permeable membrane towards solution side.
D.Electrophoresis	IV.Dispersion medium moves in an electric field.

(A)A-I, B-III, C-IV, D-II
(B)A-III, B-I, C-IV, D-II
(C)A-III, B-I, C-II, D-IV
(D)A-I, B-III, C-II, D-IV

Q24·ChemistryNumericalJEE Main 2023

The number of incorrect statement/s from the following is/are A. Water vapours are adsorbed by anhydrous calcium chloride. B. There is a decrease in surface energy during adsorption. C. As the adsorption proceeds,

\Delta H

becomes more and more negative. D. Adsorption is accompanied by decrease in entropy of the system.

Q25·ChemistryNumericalJEE Main 2023

The number of statement/s which are the characteristics of physisorption is _________. A. It is highly specific in nature. B. Enthalpy of adsorption is high. C. It decreases with increase in temperature. D. It results into unimolecular layer. E. No activation energy is needed

Q26·ChemistrySingle correctJEE Main 2023

Statement I: For colloidal particles, the values of colligative properties are of small order as compared to values shown by true solutions at same concentration. Statement II: For colloidal particles, the potential difference between the fixed layer and the diffused layer of same charges is called the electrokinetic potential or zeta potential. In the light of the above statements, choose the correct answer from the options given below:

(A)Statement I is false but Statement II is true
(B)Statement I is true but Statement II is false
(C)Both Statement I and Statement II are true
(D)Both Statement I and Statement II are false

Q27·ChemistryMultiple correctJEE Advanced 2022

The correct opion(s) related to adsorption process is (are)

(A)Chemisorption results in unimolecular layer.
(B)The enthalpy change during physisorption is in the range of 100 to 140 kJ $\mathrm{mol^{-1}}$
(C)Chemisorption is an endothermic process
(D)Lowering the temperature favours physisorption process

Q28·ChemistrySingle correctJEE Main 2022

Given below are the critical temperatures of some of the gases : Gas — Critical temperature (K) He — 5.2 CH

_{4}

— 190 CO

_{2}

— 304.2 NH

_{3}

— 405.5 The gas showing least adsorption on a definite amount of charcoal is :

(A)He
(B)CH $_{4}$
(C)CO $_{2}$
(D)NH $_{3}$

Q29·ChemistrySingle correctJEE Main 2022

100 mL of 5% (w/v) solution of NaCl in water was prepared in 250 mL beaker. Albumin from the egg was poured into NaCl solution and stirred well. This resulted in a/ an :

(A)Lyophilic sol
(B)Lyophobic sol
(C)Emulsion
(D)Precipitate

Q30·ChemistryNumericalJEE Main 2022

Among the following the number of curves not in accordance with Freundlich adsorption isotherm is _____.

Q31·ChemistrySingle correctJEE Main 2022

Match List-I with List-II. Choose the correct answer from the options given below :

List-I (Reaction)	List-II (Catalyst)
A.4NH $_3$ (g) + 5O $_2$ (g) → 4NO(g) + 6H $_2$ O(g)	I.NO(g)
B.N $_2$ (g) + 3H $_2$ (g) → 2NH $_3$ (g)	II.H $_2$ SO $_4$ ( $l$ )
C.C $_{12}$ H $_{22}$ O $_{11}$ (aq) + H $_2$ O( $l$ ) → C $_6$ H $_{12}$ O $_6$ (Glucose) + C $_6$ H $_{12}$ O $_6$ (Fructose)	III.Pt(s)
D.2SO $_2$ (g) + O $_2$ (g) → 2SO $_3$ (g)	IV.Fe(s)

(A)(A) – (II), (B) – (III), (C) – (I), (D) – (IV)
(B)(A) – (III), (B) – (II), (C) – (I), (D) – (IV)
(C)(A) – (III), (B) – (IV), (C) – (II), (D) – (I)
(D)(A) – (III), (B) – (II), (C) – (IV), (D) – (I)

Q32·ChemistrySingle correctJEE Main 2022

Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Activated charcoal adsorbs

SO_{2}

more efficiently than

CH_{4}

. Reason R : Gases with lower critical temperatures are readily adsorbed by activated charcoal. In the light of the above statements, choose the correct answer from the options given below.

(A)Both A and R are correct and R is the correct explanation of A.
(B)Both A and R are correct but R is NOT the correct explanation of A.
(C)A is correct but R is not correct.
(D)A is not correct but R is correct.

Q33·ChemistrySingle correctJEE Main 2022

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R) Assertion (A) : Dissolved substances can be removed from a colloidal solution by diffusion through a parchment paper. Reason (R) : Particles in a true solution cannot pass through parchment paper but the collodial particles can pass through the parchment paper. In the light of the above statements, choose the correct answer from the options given below:

(A)Both (A) and (R) are correct and (R) is the correct explanation of (A)
(B)Both (A) and (R) are correct but (R) is not the correct explanation of (A)
(C)(A) is correct but (R) is not correct
(D)(A) is not correct but (R) is correct

Q34·ChemistrySingle correctJEE Main 2022

Match List - I with List - II. Choose the correct answer from the options given below :

List - I (Processes/Reactions)	List - II (Catalyst)
A.2SO $_2$ (g) + O $_2$ (g) → 2SO $_3$ (g)	I.Fe(s)
B.4NH $_3$ (g) + 5O $_2$ (g) → 4NO(g) + 6H $_2$ O(g)	II.Pt(s)-Rh(s)
C.N $_2$ (g) + 3H $_2$ (g) → 2NH $_3$ (g)	III.V $_2$ O $_5$
D.Vegetable oil(l) + H $_2$ → Vegetable ghee(s)	IV.Ni(s)

(A)(A) - (III), (B) - (I), (C) - (II), (D) - (IV)
(B)(A) - (III), (B) - (II), (C) - (I), (D) - (IV)
(C)(A) - (IV), (B) - (III), (C) - (I), (D) - (II)
(D)(A) - (IV), (B) - (II), (C) - (III), (D) - (I)

Q35·ChemistrySingle correctJEE Main 2022

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Finest gold is red in colour, as the size of the particles increases, it appears purple then blue and finally gold. Assertion R : The colour of the colloidal solution depends on the wavelength of light scattered by the dispersed particles. In the light of the above statements, choose the most appropriate answer from the options given below;

(A)Both A and R are true and R is the correct explanation of A
(B)Both A and R are true but R is NOT the correct explanation of A
(C)A is true but R is false
(D)A is false but R is true

Q36·ChemistrySingle correctJEE Main 2022

Match List - I with List - II Choose the correct answer from the options given below :

List - I	List - II
A. $N_{2}(g) + 3H_{2}(g) \rightarrow 2NH_{3}(g)$	I.Cu
B. $CO(g) + 3H_{2}(g) \rightarrow CH_{4}(g) + H_{2}O(g)$	II. $Cu/ZnO - Cr_{2}O_{3}$
C. $CO(g) + H_{2}(g) \rightarrow HCHO(g)$	III. $Fe_{x}O_{y} + K_{2}O + Al_{2}O_{3}$
D. $CO(g) + 2H_{2}(g) \rightarrow CH_{3}OH(g)$	IV.Ni

(A)(A) - (II), (B) - (IV), (C) - (I), (D) - (III)
(B)(A) - (II), (B) - (I), (C) - (IV), (D) - (III)
(C)(A) - (III), (B) - (IV), (C) - (I), (D) - (II)
(D)(A) - (III), (B) - (I), (C) - (IV), (D) - (II)

Q37·ChemistrySingle correctJEE Main 2022

Which of the following is a correct statement ?

(A)Brownian motion destabilises sols.
(B)Any amount of dispersed phase can be added to emulsion without destabilising it.
(C)Mixing two oppositely charged sols in equal amount neutralises charges and stabilises colloids.
(D)Presence of equal and similar charges on colloidal particles provides stability to the colloidal solution.

Q38·ChemistrySingle correctJEE Main 2022

The Zeta potential is related to which property of colloids”

(A)Colour
(B)Tyndall effect
(C)Charge on the surface of colloidal particles
(D)Brownian movement

Q39·ChemistrySingle correctJEE Main 2022

Match List-I with List-II. Choose the correct answer from the options given below :

List-I	List-II
A.Negatively charged sol	I.Fe $_2$ O $_3$ ·xH $_2$ O
B.Macromolecular colloid	II.CdS sol
C.Positively charged sol	III.Starch
D.Cheese	IV.a gel

(A)(A) – (II), (B) – (III), (C) – (IV), (D) – (I)
(B)(A) – (II), (B) – (I), (C) – (III), (D) – (IV)
(C)(A) – (II), (B) – (III), (C) – (I), (D) – (IV)
(D)(A) – (I), (B) – (III), (C) – (II), (D) – (IV)

Q40·ChemistryNumericalJEE Main 2022

If the initial pressure of a gas is 0.03 atm, the mass of the gas adsorbed per gram of the adsorbent is ______

\times

10

^{-2}

g.

Q41·ChemistrySingle correctJEE Main 2022

Match List-I with List-II List-I (A) Lyophilic colloid (B) Emulsion (C) Positively charged (D) Negatively charged colloid List-II (I) Liquid-liquid colloid (II) protective colloid (III)

FeCl_{3}

+ NaOH (IV)

FeCl_{3}

+ hot water Choose the correct answer from the options given below:

(A)(A) – (II), (B) – (I), (C) – (IV), (D) – (III)
(B)(A) – (III), (B) – (I), (C) – (IV), (D) – (II)
(C)(A) – (II), (B) – (I), (C) – (III), (D) – (IV)
(D)(A) – (III), (B) – (II), (C) – (I), (D) – (IV)

Q42·ChemistryNumericalJEE Main 2022

2.0 g of

H_{2}

gas is adsorbed on 2.5 g of platinum powder at 300 K and 1 bar pressure. The volume of the gas adsorbed per gram of the adsorbent is ______ mL. (Given : R = 0.083 L bar

K^{-1}

mol^{-1}

)

Q43·ChemistrySingle correctJEE Main 2022

Using very little soap while washing clothes, does not serve the purpose of cleaning of clothes because

(A)soap particles remain floating in water as ions
(B)the hydrophobic part of soap is not able to take away grease
(C)the micelles are not formed due to concentration of soap, below its CMC value
(D)colloidal structure of soap in water is completely disturbed.

Q44·ChemistrySingle correctJEE Main 2022

Incorrect statement for Tyndall effect is :-

(A)The refractive indices of the dispersed phase and the dispersion medium differ greatly in magnitude.
(B)The diameter of the dispersed particles is much smaller than the wavelength of the light used.
(C)During projection of movies in the cinemas hall, Tyndall effect is noticed.
(D)It is used to distinguish a true solution from a colloidal solution.

Q45·ChemistrySingle correctJEE Main 2022

Given below are two statements : Statement I : Emulsions of oil in water are unstable and sometimes they separate into two layers on standing. Statement II :For stabilisation of an emulsion, excess of electrolyte is added. In the light of the above statements, choose the most appropriate answer from the options given below :

(A)Both Statement I and Statement II are correct.
(B)Both Statement I and Statement II are incorrect.
(C)Statement I is correct but Statement II is incorrect.
(D)Statement I is incorrect but Statement II is correct.

Q46·ChemistryNumericalJEE Main 2022

When 200 mL of 0.2 M acetic acid is shaken with 0.6 g of wood charcoal, the final concentration of acetic after adsorption is 0.1 M. The mass of acetic acid adsorbed per garm of carbon is______ g.

Q47·ChemistryMultiple correctJEE Advanced 2021

The correct statement(s) related to colloids is(are)

(A)The process of precipitating colloidal sol by an electrolyte is called peptization.
(B)Colloidal solution freezes at higher temperature than the true solution at the same concentration.
(C)Surfactants form micelle above critical micelle concentration (CMC). CMC depends on temperature
(D)Micelles are macromolecular colloids.

Q48·ChemistrySingle correctJEE Main 2021

Match List – I (Colloid Preparation Method) with List – II (Chemical Reaction). Choose the most appropriate answer from the options given below.

List-I (Colloid Preparation Method)	List-II (Chemical Reaction)
a.Hydrolysis	i.2AuCl $_{3}$ + 3HCHO + 3H $_{2}$ O → 2Au(sol) + 3HCOOH + 6HCl
b.Reduction	ii.As $_{2}$ O $_{3}$ + 3H $_{2}$ S → As $_{2}$ S $_{3}$ (sol) + 3H $_{2}$ O
c.Oxidation	iii.SO $_{2}$ + 2H $_{2}$ S → 3S(sol) + 2H $_{2}$ O
d.Double Decomposition	iv.FeCl $_{3}$ + 3H $_{2}$ O → Fe(OH) $_{3}$ (sol) + 3HCl

(A)(a)-(i), (b)-(iii), (c)-(ii), (d)-(iv)
(B)(a)-(iv), (b)-(i), (c)-(iii), (d)-(ii)
(C)(a)-(iv), (b)-(ii), (c)-(iii), (d)-(i)
(D)(a)-(i), (b)-(ii), (c)-(iv), (d)-(iii)

Q49·ChemistrySingle correctJEE Main 2021

Select the graph that correctly describes the adsorption isotherms at two temperatures

\mathrm{T_1}

and

\mathrm{T_2}

(

\mathrm{T_1} > \mathrm{T_2}

) for a gas : (x – mass of the gas adsorbed ; m – mass of adsorbent ; P – pressure)

(A)(1)
(B)(2)
(C)(3)
(D)(4)

Q50·ChemistryNumericalJEE Main 2021

\mathrm{CH_4}

is adsorbed on 1 g charcoal at 0°C following the Freundlich adsorption isotherm. 10.0 mL of

\mathrm{CH_4}

is adsorbed at 100 mm of Hg, whereas 15.0 mL is adsorbed at 200 mm of Hg. The volume of

\mathrm{CH_4}

adsorbed at 300 mm of Hg is 10

^{x}

mL. The value of x is ________

\times

10

^{-2}

. (Nearest integer) [Use

\log_{10}2 = 0.3010

,

\log_{10}3 = 0.4771

]

Q51·ChemistrySingle correctJEE Main 2021

Lyophilic sols are more stable than lyophobic sols because :

(A)there is a strong electrostatic repulsion between the negatively charged colloidal particles.
(B)the colloidal particles have positive charge.
(C)the colloidal particles have no charge.
(D)the colloidal particles are solvated.

Q52·ChemistrySingle correctJEE Main 2021

Tyndall effect is more effectively shown by :

(A)true solution
(B)lyophilic colloid
(C)lyophobic colloid
(D)suspension

Q53·ChemistrySingle correctJEE Main 2021

Acidic ferric chloride solution on treatment with excess of potassium ferrocyanide gives a Prussian blue coloured colloidal species. It is :

(A) $\mathrm{Fe_4[Fe(CN)_6]_3}$
(B) $\mathrm{K_5Fe[Fe(CN)_6]_2}$
(C) $\mathrm{HFe[Fe(CN)_6]}$
(D) $\mathrm{KFe[Fe(CN)_6]}$

Q54·ChemistrySingle correctJEE Main 2021

The sol given below with negatively charged colloidal particles is :

(A) $\mathrm{FeCl_3}$ added to hot water
(B)KI added to $\mathrm{AgNO_3}$ solution
(C) $\mathrm{AgNO_3}$ added to KI solution
(D) $\mathrm{Al_2O_3.xH_2O}$ in water

Q55·ChemistrySingle correctJEE Main 2021

Which one of the following is correct for the adsorption of a gas at a given temperature on a solid surface?

(A) $\Delta H > 0,\ \Delta S > 0$
(B) $\Delta H > 0,\ \Delta S < 0$
(C) $\Delta H < 0,\ \Delta S < 0$
(D) $\Delta H < 0,\ \Delta S > 0$

Q56·ChemistrySingle correctJEE Main 2021

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: SO

_2

(g) is adsorbed to a larger extent than H

_2

(g) on activated charcoal. Reason R: SO

_2

(g) has a higher critical temperature than H

_2

(g) In the light of the above statements, choose the most appropriate answer from the option given below.

(A)Both A and R are correct but R is not the correct explanation of A.
(B)A is not correct but R is correct.
(C)A is correct but R is not correct.
(D)Both A and R are correct and R is the correct explanation of A.

Q57·ChemistryNumericalJEE Main 2021

CO_2

gas adsorbs on charcoal following Freundlich adsorption isotherm. For a given amount of charcoal, the mass of

CO_2

adsorbed becomes 64 times when the pressure of

CO_2

is doubled. The value of n in the Freundlich isotherm equation is ________

\times 10^{-2}

. (Round off to the Nearest integer)

Q58·ChemistrySingle correctJEE Main 2021

Match List – I with List – II: Choose the most appropriate answer from the option given below:

List-I (Example of Colloids)	List-II (Classification)
a.Cheese	i.dispersion of liquid in liquid
b.Pumice stone	ii.dispersion of liquid in gas
c.Hair cream	iii.dispersion of gas in solid
d.Cloud	iv.dispersion of liquid in solid

(A)(a) – (iii), (b) –(iv), (c) –(i), (d) –(ii)
(B)(a) –(iv), (b) –(iii), (c) –(ii), (d) – (i)
(C)(a) –(iv), (b) –(iii), (c) –(i), (d) –(ii)
(D)(a) –(iv), (b) –(i), (c) –(iii), (d) –(ii)

Q59·ChemistrySingle correctJEE Main 2021

When silver nitrate solution is added to potassium iodide solution then the sol produced is:

(A)AgI/I⁻
(B) $AgNO_3/NO_3^-$
(C) $KI/NO_3^-$
(D) $AgI/Ag^+$

Q60·ChemistrySingle correctJEE Main 2021

The conditions given below are in the context of observing Tyndall effect in colloidal solutions: (a) The diameter of the colloidal particles is comparable to the wavelength of light used. (b) The diameter of the colloidal particles in much smaller than the wavelength of light used. (c) The diameter of the colloidal particles is much larger than the wavelength of light used. (d) The refractive indices of the dispersed phase and the dispersion medium are comparable. (e) The dispersed phase has a very different refractive index from the dispersion medium. Choose the most appropriate conditions from the options given below.

(A)(a) and (d) only
(B)(a) and (e) only
(C)(c) and (d) only
(D)(b) and (e) only

Q61·ChemistryNumericalJEE Main 2021

100 ml of 0.0018% (w/v) solution of

\mathrm{Cl}^-

ion was the minimum concentration of

\mathrm{Cl}^-

required to precipitate a negative sol in one h. The coagulating value of

\mathrm{Cl}^-

ion is ________. (Nearest integer)

Q62·ChemistrySingle correctJEE Main 2021

Match List-I with List-II Choose the most appropriate answer from the options given below -

List-I (process)	List-II (catalyst)
a.Deacron's process	i.ZSM-5
b.Contact process	ii.CuCl $_{2}$
c.Cracking of hydrocarbons	iii.Particles 'Ni'
d.Hydrogenation of vegetable oils	iv.V $_{2}$ O $_{5}$

(A)a-ii, b-iv, c-i, d-iii
(B)a-i, b-iii, c-ii, d-iv
(C)a-iii, b-i, c-iv, d-ii
(D)a-iv, b-ii, c-i, d-iii

Q63·ChemistrySingle correctJEE Main 2021

The charges on the colloidal CdS sol and TiO

_{2}

sol are, respectively :

(A)positive and positive
(B)positive and negative
(C)negative and negative
(D)negative and positive

Q64·ChemistrySingle correctJEE Main 2021

A colloidal system consisting of a gas dispersed in a solid is called a/an :

(A)solid sol
(B)gel
(C)aerosol
(D)foam

Q65·ChemistrySingle correctJEE Main 2021

For the coagulation of a negative sol, the species below, that has the highest flocculating power is :

(A)SO $_{4}^{2-}$
(B)Ba $^{2+}$
(C)Na $^{+}$
(D)PO $_{4}^{3-}$

Q66·ChemistrySingle correctJEE Main 2021

The INCORRECT statements below regarding colloidal solutions is :

(A)A colloidal solution shows colligative properties.
(B)An ordinary filter paper can stop the flow of colloidal particles.
(C)The flocculating power of Al $^{3+}$ is more than that of Na $^{+}$ .
(D)A colloidal solution shows Brownian motion of colloidal particles.

Q67·ChemistrySingle correctJEE Main 2021

The nature of charge on resulting colloidal particles when FeCl

_3

is added to excess of hot water is:

(A)positive
(B)neutral
(C)sometimes positive and sometimes negative
(D)negative

Q68·ChemistryNumericalJEE Main 2021

3.12 g of oxygen is adsorbed on 1.2 g of platinum metal. The value of oxygen adsorbed per gram of the adsorbent at 1 atm and 300 K in L is ________. [R = 0.0821 L atm K

^{-1}

mol

^{-1}

]

Q69·ChemistrySingle correctJEE Main 2021

Which one of the following statements is FALSE for hydrophilic sols ?

(A)These sols are reversible in nature
(B)The sols cannot be easily coagulated
(C)They do not require electrolytes for stability.
(D)Their viscosity is of the order of that of H2O

Q70·ChemistrySingle correctJEE Main 2021

In Freundlich adsorption isotherm at moderate pressure, the extent of adsorption

\left(\dfrac{x}{m}\right)

is directly proportional to P

^{x}

. The value of x is:

(A)∞
(B)1
(C)zero
(D) $\dfrac{1}{n}$

Q71·ChemistrySingle correctJEE Main 2021

Most suitable salt which can be used for efficient clotting of blood will be :

(A) $Mg(HCO_{3})_{2}$
(B) $FeSO_{4}$
(C) $NaHCO_{3}$
(D) $FeCl_{3}$

Q72·ChemistrySingle correctJEE Main 2021

In Freundlich adsorption isotherm, slope of AB line is :

(A) $\frac{1}{n}$ with $\left(\frac{1}{n} = 0 \text{ to } 1\right)$
(B) $\log \frac{1}{n}$ with $(n<1)$
(C) $\log n$ with $(n>1)$
(D) $n$ with $(n, 0.1 \text{ to } 0.5)$

Q73·ChemistryNumericalJEE Main 2020

For Freudlich adsorption isotherm, a plot of log (x/m) (y-axis) and log p (x-axis) gives a straight line. The intercept and slope for the line is 0.4771 and 2, respectively. The mass of gas adsorbed per gram of adsorbent if the initial pressure is 0.04 atm, is __________ × 10

^{-4}

g. (log 3 = 0.4771)

Q74·ChemistrySingle correctJEE Main 2020

Kraft temperature is the temperature:

(A)below which the aqueous solution of detergents starts freezing
(B)below which the formation of micelles takes place
(C)above which the aqueous solution of detergents starts boiling
(D)above which the formation of micelles takes place.

Q75·ChemistrySingle correctJEE Main 2020

Adsorption of a gas follows Freundlich adsorption isotherm. If x is the mass of the gas adsorbed on mass m of the adsorbent, the correct plot of

\dfrac{x}{m}

versus p is:

(A)(A)
(B)(B)
(C)(C)
(D)(D)

Q76·ChemistrySingle correctJEE Main 2020

A sample of red ink (a colloidal suspension) is prepared by mixing eosine dye, egg white, HCHO and water. The component which ensures stability of the ink sample is :

(A)Egg white
(B)HCHO
(C)Water
(D)Eosin dye

Q77·ChemistrySingle correctJEE Main 2020

Match the following:

Column I	Column II
(i).Foam	(a).smoke
(ii).Gel	(b).cell fluid
(iii).Aerosol	(c).jellies
(iv).Emulsion	(d).rubber
	(e).froth
	(f).milk

(A)(i)-(d), (ii)-(b), (iii)-(a), (iv)-(e)
(B)(i)-(d), (ii)-(b), (iii)-(e), (iv)-(f)
(C)(i)-(b), (ii)-(c), (iii)-(e), (iv)-(d)
(D)(i)-(e), (ii)-(c), (iii)-(a), (iv)-(f)

Q78·ChemistrySingle correctJEE Main 2020

Tyndall effect is observed when

(A)The diameter of dispersed particles is similar to the wavelength of light used.
(B)The diameter of dispersed particles is much larger than the wavelength of light used.
(C)The refractive index of dispersed phase is greater than that of the dispersion medium.
(D)The diameter of dispersed particles is much smaller than the wavelength of light used.

Q79·ChemistrySingle correctJEE Main 2020

An ionic micelles is formed on the addition of:

(A)(A)
(B)sodium stearate to pure toluene
(C)liquid diethyl ether to aqueous NaCl solution
(D)(D)

Q80·ChemistrySingle correctJEE Main 2020

A mixture of gases O

_2

, H

_2

and CO are taken in a closed vessel containing charcoal. The graph that represents the correct behaviour of pressure with time is:

(A)(A)
(B)(B)
(C)(C)
(D)(D)

Q81·ChemistrySingle correctJEE Main 2020

As per Hardy-Schulze formulation, the flocculation values of the following for ferric hydroxide sol are in the order :

(A)AlCl $_{3}$ > K $_{3}$ [Fe(CN) $_{6}$ ] > K $_{2}$ CrO $_{4}$ > KBr = KNO $_{3}$
(B)K $_{3}$ [Fe(CN) $_{6}$ ] < K $_{2}$ CrO $_{4}$ < KBr = KNO $_{3}$ = AlCl $_{3}$
(C)K $_{3}$ [Fe(CN) $_{6}$ ] < K $_{2}$ CrO $_{4}$ < AlCl $_{3}$ < KBr < KNO $_{3}$
(D)K $_{3}$ [Fe(CN) $_{6}$ ] > AlCl $_{3}$ > K $_{2}$ CrO $_{4}$ > KBr > KNO $_{3}$

Q82·ChemistryNumericalJEE Main 2020

The flocculation value of HCl for arsenic sulphide sol is 30 m mol L

^{-1}

. If

H_2SO_4

is used for the flocculation of arsenic sulphide, the amount, in grams of

H_2SO_4

in 250 mL required for the above purpose is __________ (Molecular mass of

H_2SO_4

= 98 g/mol)

Q83·ChemistrySingle correctJEE Advanced 2019

Molar conductivity (

\Lambda_{m}

) of aqueous solution of sodium stearate, which behaves as a strong electrolyte, is recorded at varying concentrations (c) of sodium stearate. Which one of the following plots provides the correct representation of micelle formation in the solution? (critical micelle concentration (CMC) is marked with an arrow in the figures

(A)(A)
(B)(B)
(C)(C)
(D)(D)

Q84·ChemistrySingle correctJEE Main 2019

Among the following, the INCORRECT statement about colloids is :

(A)The range of diameters of colloidal particles is between 1 and 1000 nm
(B)The osmotic pressure of a colloidal solution is of higher order than the true solution at the same concentration
(C)They can scatter light
(D)They are larger than small molecules and have high molar mass

Q85·ChemistrySingle correctJEE Main 2019

Peptization is a :

(A)process of converting soluble particles to form colloidal solution
(B)process of converting precipitate into colloidal solution
(C)process of converting a colloidal solution into precipitate
(D)process of bringing colloidal molecule into solution

Q86·ChemistrySingle correctJEE Main 2019

A gas undergoes physical adsorption on a surface and follows the given Freundlich adsorption isotherm equation

\frac{x}{m} = kp^{0.5}

Adsorption of the gas increases with:

(A)Increase in p and decrease in T
(B)Increase in p and increase in T
(C)Decrease in p and increase in T
(D)Decrease in p and decrease in T

Q87·ChemistrySingle correctJEE Main 2019

The correct option among the following is:

(A)Colloidal particles in lyophobic sols can be precipitated by electrophoresis.
(B)Brownian motion in colloidal solution is faster the viscosity of the solution is very high.
(C)Colloidal medicines are more effective because they have small surface area.
(D)Addition of alum to water makes it unfit for drinking.

Q88·ChemistrySingle correctJEE Main 2019

Match the catalysis(Column – I) with products (Column-II)

Column-I (Catalyst)	Column-II (Product)
a. $V_2O_5$	i.Polyethylene
b. $TiCl_4/Al(Me)_3$	ii.Ethanal
c. $PdCl_2$	iii. $H_2SO_4$
d.Iron oxide	iv. $NH_3$

(A)(a)-(iii); (b)-(iv); (c)-(i); (d)-(ii)
(B)(a)-(iv); (b)-(iii); (c)-(ii); (d)-(i)
(C)(a)-(ii); (b)-(iii); (c)-(i); (d)-(iv)
(D)(a)-(iii); (b)-(i); (c)-(ii); (d)-(iv)

Q89·ChemistrySingle correctJEE Main 2019

The aerosol is a kind of colloid in which:

(A)solid is dispersed in gas
(B)gas is dispersed in solid
(C)liquid is dispersed in water
(D)gas is dispersed in liquid

Q90·ChemistrySingle correctJEE Main 2019

Adsorption of a gas follows Freundlich adsorption isotherm. x is the mass of the gas adsorbed on mass m of the adsorbent. The plot of

\log \dfrac{x}{m}

versus

\log p

is shown in the given graph,

\dfrac{x}{m}

is proportional to:

(A) $p^{2/3}$
(B) $p^2$
(C) $p^3$
(D) $p^{3/2}$

Q91·ChemistrySingle correctJEE Main 2019

0.27 g of a long chain fatty acid was dissolved in 100

cm^{3}

of hexane. 10 mL of this solution was added dropwise to the surface of water in a round watch glass. Hexane evaporates and a monolayer is formed. The distance from edge to centre of the watch glass is 10 cm. What is the height of the monolayer? [Density of fatty acid

=0.9\\ g\\ cm^{-3}

,

\pi=3

]

(A) $10^{-4}$ m
(B) $10^{-8}$ m
(C) $10^{-2}$ m
(D) $10^{-6}$ m

Q92·ChemistrySingle correctJEE Main 2019

Among the following, the false statement is :

(A)It is possible to cause artificial rain by throwing electrified sand carrying charge opposite to the one on clouds from an aeroplane.
(B)Tyndall effect can be used to distinguish between a colloidal solution and a true solution.
(C)Lyophilic sol can be coagulated by adding an electrolyte.
(D)Latex is a colloidal solution of rubber particles which are positively charged.

Q93·ChemistrySingle correctJEE Main 2019

An example of solid sol is:

(A)Paint
(B)Gem stones
(C)Butter
(D)Hair cream

Q94·ChemistrySingle correctJEE Main 2019

Among the colloids cheese (C), milk (M) and smoke (S), the correct combination of the dispersed phase and dispersion medium, respectively is:

(A)C: liquid in solid; M: liquid in solid; S: solid in gas
(B)C : liquid in solid; M: liquid in liquid; S: solid in gas
(C)C : solid in liquid ; M : liquid in liquid ; S : gas in solid
(D)C : solid in liquid ; M : solid in liquid; S : solid in gas

Q95·ChemistrySingle correctJEE Main 2019

Which of the following is not an example of heterogeneous catalytic reaction?

(A)Ostwald's process
(B)Combustion of coal
(C)Hydrogenation of vegetable oils
(D)Haber's process

Q96·ChemistrySingle correctJEE Main 2019

Adsorption of a gas follows Freundlich adsorption isotherm. In the given plot, x is the mass of gas adsorbed on mass m of the adsorbent at pressure p.

\frac{x}{m}

is proportional to

(A)p $^{2}$
(B)p $^{1/4}$
(C)p $^{1/2}$
(D)p

Q97·ChemistrySingle correctJEE Main 2019

For coagulation of arsenious sulphide sol, which one of the following salt solution will be most effective?

(A)BaCl $_2$
(B)AlCl $_3$
(C)NaCl
(D)Na $_3$ PO $_4$

Q98·ChemistrySingle correctJEE Main 2019

The correct match between item I and item II is

Item I	Item II
a.Benzaldehyde	p.Mobile phase
b.Alumina	q.Adsorbent
c.Acetonitrile	r.Adsorbate

(A)a $\rightarrow$ q, b $\rightarrow$ p, c $\rightarrow$ r
(B)a $\rightarrow$ r, b $\rightarrow$ q, c $\rightarrow$ p
(C)a $\rightarrow$ q, b $\rightarrow$ r, c $\rightarrow$ p
(D)a $\rightarrow$ p, b $\rightarrow$ r, c $\rightarrow$ q

Q99·ChemistryMultiple correctJEE Advanced 2017

The correct statement(s) about surface properties is(are)

(A)Adsorption is accompanied by decrease in enthalpy and decrease in entropy of the system
(B)The critical temperatures of ethane and nitrogen are 563 K and 126 K, respectively. The adsorption of ethane will be more than that of nitrogen on same amount of activated charcoal at a given temperature
(C)Cloud is an emulsion type of colloid in which liquid is dispersed phase and gas is dispersion medium
(D)Brownian motion of colloidal particles does not depend on the size of the particles but depends on viscosity of the solution

Q100·ChemistrySingle correctJEE Advanced 2016

The qualitative sketches I, II and III given below show the variation of surface tension with molar concentration of three different aqueous solutions of KCl,

CH_{3}OH

and

CH_{3}(CH_{2})_{11}OSO_{3}^{-}Na^{+}

at room temperature. The correct assignment of the sketches is

(A)I : KCl; II : $CH_{3}OH$ ; III : $CH_{3}(CH_{2})_{11}OSO_{3}^{-}Na^{+}$
(B)I : $CH_{3}(CH_{2})_{11}OSO_{3}^{-}Na^{+}$ ; II : $CH_{3}OH$ ; III : KCl
(C)I : KCl; II : $CH_{3}(CH_{2})_{11}OSO_{3}^{-}Na^{+}$ ; III : $CH_{3}OH$
(D)I : $CH_{3}OH$ ; II : KCl; III : $CH_{3}(CH_{2})_{11}OSO_{3}^{-}Na^{+}$

Q101·ChemistryMultiple correctJEE Advanced 2015

When

\mathrm{O_{2}}

is adsorbed on a metallic surface, electron transfer occurs from the metal to

\mathrm{O_{2}}

. The

\mathbf{TRUE}

statement(s) regarding this adsorption is(are)

(A) $\mathrm{O_{2}}$ is physisorbed
(B)heat is released
(C)occupancy of $\pi^{*}_{2\mathrm{p}}$ of $\mathrm{O_{2}}$ is increased
(D)bond length of $\mathrm{O_{2}}$ is increased

Q102·ChemistrySingle correctJEE Advanced 2013

Methylene blue, from its aqueous solution, is adsorbed on activated charcoal at 25

^{\circ}

C. For this process, the correct statement is

(A)The adsorption requires activation at 25 $^{\circ}$ C.
(B)The adsorption is accompanied by a decrease in enthalpy.
(C)The adsorption increases with increase of temperature.
(D)The adsorption is irreversible.

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