JEE Mains Previous Year Questions (2021-2024): Solutions | Chapter-wise Tests for JEE Main & Advanced PDF Download

 Page 1


Numerical 
 
 
Q.1. The vapour pressure of 30%(w/v) aqueous solution of 
glucose is __________  mm Hg at 25°C. 
 
[Given : The density of 30% (w/v), aqueous solution of glucose 
is   1.2 g cm
-3
 and vapour pressure of pure water is   24 mm Hg.] 
 
(Molar mass of glucose is   180 g mol
-1
.) 
95  g mol-1 respectively. 
 
 
JEE Main 2023 (Online) 13th April Evening Shift
JEE Main 2023 (Online) 15th April Morning Shift
 
 
Q.2. Sea water contains  29.25% NaCl and  19% MgCl2 by weight 
of solution. The normal boiling point of the sea water is 
_____________ °C (Nearest integer) 
Q.3. Solution of    12 g of non-electrolyte (A) prepared by 
dissolving it in    1000 mL of water exerts the same osmotic 
pressure as that of    0.05 M glucose solution at the same 
temperature. The empirical formula of A is CH2O. The molecular 
mass of A is __________ g. (Nearest integer) 
Assume 100% ionization for both NaCl and MgCl2 
Given :    Kb(H2O)=0.52 K kg mol
-1
 
Molar mass of NaCl and MgCl2 is 58.5 and 
Page 2


Numerical 
 
 
Q.1. The vapour pressure of 30%(w/v) aqueous solution of 
glucose is __________  mm Hg at 25°C. 
 
[Given : The density of 30% (w/v), aqueous solution of glucose 
is   1.2 g cm
-3
 and vapour pressure of pure water is   24 mm Hg.] 
 
(Molar mass of glucose is   180 g mol
-1
.) 
95  g mol-1 respectively. 
 
 
JEE Main 2023 (Online) 13th April Evening Shift
JEE Main 2023 (Online) 15th April Morning Shift
 
 
Q.2. Sea water contains  29.25% NaCl and  19% MgCl2 by weight 
of solution. The normal boiling point of the sea water is 
_____________ °C (Nearest integer) 
Q.3. Solution of    12 g of non-electrolyte (A) prepared by 
dissolving it in    1000 mL of water exerts the same osmotic 
pressure as that of    0.05 M glucose solution at the same 
temperature. The empirical formula of A is CH2O. The molecular 
mass of A is __________ g. (Nearest integer) 
Assume 100% ionization for both NaCl and MgCl2 
Given :    Kb(H2O)=0.52 K kg mol
-1
 
Molar mass of NaCl and MgCl2 is 58.5 and 
Given : R = 0.083 L bar K
-1
 mol
-1
 
 
JEE Main 2023 (Online) 10th April Evening Shift 
 
Q.7. If the degree of dissociation of aqueous solution of weak 
monobasic acid is determined to be 0.3, then the observed 
freezing point will be ___________% higher than the 
expected/theoretical freezing point. (Nearest integer) 
Given : Vapour pressure of water at 38°C is  50 mm Hg 
 
JEE Main 2023 (Online) 12th April Morning Shift 
 
Q.5. 0.004 M K2SO4 solution is isotonic with 0.01 M glucose 
solution. Percentage dissociation of K2SO4 is ___________ (Nearest 
integer) 
 
JEE Main 2023 (Online) 11th April Morning Shift 
 
Q.6. An aqueous solution of volume  300 cm
3
 contains  0.63 g of 
protein. The osmotic pressure of the solution at  300 K is 1.29 
mbar. The molar mass of the protein is ___________  g mol-1 
Q.9. The vapour pressure vs. temperature curve for a solution 
solvent system is shown below.
JEE Main 2023 (Online) 8th April Evening Shift 
 
 
JEE Main 2023 (Online) 10th April Morning Shift 
 
Q.8. If the boiling points of two solvents X and Y (having same 
molecular weights) are in the ratio 2:1 and their enthalpy of 
vaporizations are in the ratio 1:2, then the boiling point elevation 
constant of X is m? times the boiling point elevation constant of Y. 
The value of m is ____________ (nearest integer) 
JEE Main 2023 (Online) 13th April Morning Shift  
 
Q.4. 80 mole percent of MgCl2 is dissociated in aqueous solution. 
The vapour pressure of  1.0 molal aqueous solution 
of MgCl2 at 38°C is ____________    mm Hg. (Nearest integer) 
Page 3


Numerical 
 
 
Q.1. The vapour pressure of 30%(w/v) aqueous solution of 
glucose is __________  mm Hg at 25°C. 
 
[Given : The density of 30% (w/v), aqueous solution of glucose 
is   1.2 g cm
-3
 and vapour pressure of pure water is   24 mm Hg.] 
 
(Molar mass of glucose is   180 g mol
-1
.) 
95  g mol-1 respectively. 
 
 
JEE Main 2023 (Online) 13th April Evening Shift
JEE Main 2023 (Online) 15th April Morning Shift
 
 
Q.2. Sea water contains  29.25% NaCl and  19% MgCl2 by weight 
of solution. The normal boiling point of the sea water is 
_____________ °C (Nearest integer) 
Q.3. Solution of    12 g of non-electrolyte (A) prepared by 
dissolving it in    1000 mL of water exerts the same osmotic 
pressure as that of    0.05 M glucose solution at the same 
temperature. The empirical formula of A is CH2O. The molecular 
mass of A is __________ g. (Nearest integer) 
Assume 100% ionization for both NaCl and MgCl2 
Given :    Kb(H2O)=0.52 K kg mol
-1
 
Molar mass of NaCl and MgCl2 is 58.5 and 
Given : R = 0.083 L bar K
-1
 mol
-1
 
 
JEE Main 2023 (Online) 10th April Evening Shift 
 
Q.7. If the degree of dissociation of aqueous solution of weak 
monobasic acid is determined to be 0.3, then the observed 
freezing point will be ___________% higher than the 
expected/theoretical freezing point. (Nearest integer) 
Given : Vapour pressure of water at 38°C is  50 mm Hg 
 
JEE Main 2023 (Online) 12th April Morning Shift 
 
Q.5. 0.004 M K2SO4 solution is isotonic with 0.01 M glucose 
solution. Percentage dissociation of K2SO4 is ___________ (Nearest 
integer) 
 
JEE Main 2023 (Online) 11th April Morning Shift 
 
Q.6. An aqueous solution of volume  300 cm
3
 contains  0.63 g of 
protein. The osmotic pressure of the solution at  300 K is 1.29 
mbar. The molar mass of the protein is ___________  g mol-1 
Q.9. The vapour pressure vs. temperature curve for a solution 
solvent system is shown below.
JEE Main 2023 (Online) 8th April Evening Shift 
 
 
JEE Main 2023 (Online) 10th April Morning Shift 
 
Q.8. If the boiling points of two solvents X and Y (having same 
molecular weights) are in the ratio 2:1 and their enthalpy of 
vaporizations are in the ratio 1:2, then the boiling point elevation 
constant of X is m? times the boiling point elevation constant of Y. 
The value of m is ____________ (nearest integer) 
JEE Main 2023 (Online) 13th April Morning Shift  
 
Q.4. 80 mole percent of MgCl2 is dissociated in aqueous solution. 
The vapour pressure of  1.0 molal aqueous solution 
of MgCl2 at 38°C is ____________    mm Hg. (Nearest integer) 
 
The boiling point of the solvent is __________ °C. 
JEE Main 2023 (Online) 8th April Morning Shift 
 
Q.10. Mass of Urea (NH2CONH2) required to be dissolved 
in  1000 g of water in order to reduce the vapour pressure of 
water by 25% is _________ g. (Nearest integer) 
Given: Molar mass of N, C, O and H 
are 14,12,16 and   1 g mol
-1
 respectively 
 
JEE Main 2023 (Online) 6th April Morning Shift 
 
Q.11. 20% of acetic acid is dissociated when its  5 g is added 
to  500 mL of water. The depression in freezing point of such 
water is _________ ×10
-3°
C. 
Atomic mass of C,H and O are 12,1 and 16 a.m.u. respectively. 
[Given : Molal depression constant and density of water 
are    1.86 K kg mol
-1
 and   1 g cm
-3
 respectively.] 
 
JEE Main 2023 (Online) 1st February Evening Shift 
Q.12. 25 mL of an aqueous solution of KCl was found to require 20 
mL of 1 M AgNO3 solution when titrated using K2CrO4 as an 
indicator. What is the depression in freezing point of KCl solution 
of the given concentration? _________ (Nearest integer). 
Page 4


Numerical 
 
 
Q.1. The vapour pressure of 30%(w/v) aqueous solution of 
glucose is __________  mm Hg at 25°C. 
 
[Given : The density of 30% (w/v), aqueous solution of glucose 
is   1.2 g cm
-3
 and vapour pressure of pure water is   24 mm Hg.] 
 
(Molar mass of glucose is   180 g mol
-1
.) 
95  g mol-1 respectively. 
 
 
JEE Main 2023 (Online) 13th April Evening Shift
JEE Main 2023 (Online) 15th April Morning Shift
 
 
Q.2. Sea water contains  29.25% NaCl and  19% MgCl2 by weight 
of solution. The normal boiling point of the sea water is 
_____________ °C (Nearest integer) 
Q.3. Solution of    12 g of non-electrolyte (A) prepared by 
dissolving it in    1000 mL of water exerts the same osmotic 
pressure as that of    0.05 M glucose solution at the same 
temperature. The empirical formula of A is CH2O. The molecular 
mass of A is __________ g. (Nearest integer) 
Assume 100% ionization for both NaCl and MgCl2 
Given :    Kb(H2O)=0.52 K kg mol
-1
 
Molar mass of NaCl and MgCl2 is 58.5 and 
Given : R = 0.083 L bar K
-1
 mol
-1
 
 
JEE Main 2023 (Online) 10th April Evening Shift 
 
Q.7. If the degree of dissociation of aqueous solution of weak 
monobasic acid is determined to be 0.3, then the observed 
freezing point will be ___________% higher than the 
expected/theoretical freezing point. (Nearest integer) 
Given : Vapour pressure of water at 38°C is  50 mm Hg 
 
JEE Main 2023 (Online) 12th April Morning Shift 
 
Q.5. 0.004 M K2SO4 solution is isotonic with 0.01 M glucose 
solution. Percentage dissociation of K2SO4 is ___________ (Nearest 
integer) 
 
JEE Main 2023 (Online) 11th April Morning Shift 
 
Q.6. An aqueous solution of volume  300 cm
3
 contains  0.63 g of 
protein. The osmotic pressure of the solution at  300 K is 1.29 
mbar. The molar mass of the protein is ___________  g mol-1 
Q.9. The vapour pressure vs. temperature curve for a solution 
solvent system is shown below.
JEE Main 2023 (Online) 8th April Evening Shift 
 
 
JEE Main 2023 (Online) 10th April Morning Shift 
 
Q.8. If the boiling points of two solvents X and Y (having same 
molecular weights) are in the ratio 2:1 and their enthalpy of 
vaporizations are in the ratio 1:2, then the boiling point elevation 
constant of X is m? times the boiling point elevation constant of Y. 
The value of m is ____________ (nearest integer) 
JEE Main 2023 (Online) 13th April Morning Shift  
 
Q.4. 80 mole percent of MgCl2 is dissociated in aqueous solution. 
The vapour pressure of  1.0 molal aqueous solution 
of MgCl2 at 38°C is ____________    mm Hg. (Nearest integer) 
 
The boiling point of the solvent is __________ °C. 
JEE Main 2023 (Online) 8th April Morning Shift 
 
Q.10. Mass of Urea (NH2CONH2) required to be dissolved 
in  1000 g of water in order to reduce the vapour pressure of 
water by 25% is _________ g. (Nearest integer) 
Given: Molar mass of N, C, O and H 
are 14,12,16 and   1 g mol
-1
 respectively 
 
JEE Main 2023 (Online) 6th April Morning Shift 
 
Q.11. 20% of acetic acid is dissociated when its  5 g is added 
to  500 mL of water. The depression in freezing point of such 
water is _________ ×10
-3°
C. 
Atomic mass of C,H and O are 12,1 and 16 a.m.u. respectively. 
[Given : Molal depression constant and density of water 
are    1.86 K kg mol
-1
 and   1 g cm
-3
 respectively.] 
 
JEE Main 2023 (Online) 1st February Evening Shift 
Q.12. 25 mL of an aqueous solution of KCl was found to require 20 
mL of 1 M AgNO3 solution when titrated using K2CrO4 as an 
indicator. What is the depression in freezing point of KCl solution 
of the given concentration? _________ (Nearest integer). 
(Given :    Kf=2.0 K kg mol
-1
) 
Assume 1) 100% ionization and 2) density of the aqueous 
solution as 1 g mL
-1
 
 
JEE Main 2023 (Online) 1st February Morning Shift 
Q.13. At 27°C, a solution containing  2.5 g of solute in  250.0 mL of 
solution exerts an osmotic pressure of  400 Pa. The molar mass of 
the solute is ___________  g mol
-1
 (Nearest integer) 
(Given :     R=0.083 L bar K
-1
 mol
-1
) 
 
JEE Main 2023 (Online) 31st January Morning Shift 
Q.14. Lead storage battery contains 38% by weight solution 
of H2SO4. The van't Hoff factor is 2.67 at this concentration. The 
temperature in Kelvin at which the solution in the battery will 
freeze is ________. (Nearest integer). 
 
 
JEE Main 2023 (Online) 30th January Evening Shift 
 
Q.15. A solution containing  2 g of a non-volatile solute in  20 g of 
water boils at  373.52 K. The molecular mass of the solute is 
___________  g mol-1. (Nearest integer) 
Given, water boils at     
 
JEE Main 2023 (Online) 30th January Morning Shift 
Q.16. The number of pairs of the solutions having the same value 
of the osmotic pressure from the following is _________. 
(Assume 100% ionization) 
Page 5


Numerical 
 
 
Q.1. The vapour pressure of 30%(w/v) aqueous solution of 
glucose is __________  mm Hg at 25°C. 
 
[Given : The density of 30% (w/v), aqueous solution of glucose 
is   1.2 g cm
-3
 and vapour pressure of pure water is   24 mm Hg.] 
 
(Molar mass of glucose is   180 g mol
-1
.) 
95  g mol-1 respectively. 
 
 
JEE Main 2023 (Online) 13th April Evening Shift
JEE Main 2023 (Online) 15th April Morning Shift
 
 
Q.2. Sea water contains  29.25% NaCl and  19% MgCl2 by weight 
of solution. The normal boiling point of the sea water is 
_____________ °C (Nearest integer) 
Q.3. Solution of    12 g of non-electrolyte (A) prepared by 
dissolving it in    1000 mL of water exerts the same osmotic 
pressure as that of    0.05 M glucose solution at the same 
temperature. The empirical formula of A is CH2O. The molecular 
mass of A is __________ g. (Nearest integer) 
Assume 100% ionization for both NaCl and MgCl2 
Given :    Kb(H2O)=0.52 K kg mol
-1
 
Molar mass of NaCl and MgCl2 is 58.5 and 
Given : R = 0.083 L bar K
-1
 mol
-1
 
 
JEE Main 2023 (Online) 10th April Evening Shift 
 
Q.7. If the degree of dissociation of aqueous solution of weak 
monobasic acid is determined to be 0.3, then the observed 
freezing point will be ___________% higher than the 
expected/theoretical freezing point. (Nearest integer) 
Given : Vapour pressure of water at 38°C is  50 mm Hg 
 
JEE Main 2023 (Online) 12th April Morning Shift 
 
Q.5. 0.004 M K2SO4 solution is isotonic with 0.01 M glucose 
solution. Percentage dissociation of K2SO4 is ___________ (Nearest 
integer) 
 
JEE Main 2023 (Online) 11th April Morning Shift 
 
Q.6. An aqueous solution of volume  300 cm
3
 contains  0.63 g of 
protein. The osmotic pressure of the solution at  300 K is 1.29 
mbar. The molar mass of the protein is ___________  g mol-1 
Q.9. The vapour pressure vs. temperature curve for a solution 
solvent system is shown below.
JEE Main 2023 (Online) 8th April Evening Shift 
 
 
JEE Main 2023 (Online) 10th April Morning Shift 
 
Q.8. If the boiling points of two solvents X and Y (having same 
molecular weights) are in the ratio 2:1 and their enthalpy of 
vaporizations are in the ratio 1:2, then the boiling point elevation 
constant of X is m? times the boiling point elevation constant of Y. 
The value of m is ____________ (nearest integer) 
JEE Main 2023 (Online) 13th April Morning Shift  
 
Q.4. 80 mole percent of MgCl2 is dissociated in aqueous solution. 
The vapour pressure of  1.0 molal aqueous solution 
of MgCl2 at 38°C is ____________    mm Hg. (Nearest integer) 
 
The boiling point of the solvent is __________ °C. 
JEE Main 2023 (Online) 8th April Morning Shift 
 
Q.10. Mass of Urea (NH2CONH2) required to be dissolved 
in  1000 g of water in order to reduce the vapour pressure of 
water by 25% is _________ g. (Nearest integer) 
Given: Molar mass of N, C, O and H 
are 14,12,16 and   1 g mol
-1
 respectively 
 
JEE Main 2023 (Online) 6th April Morning Shift 
 
Q.11. 20% of acetic acid is dissociated when its  5 g is added 
to  500 mL of water. The depression in freezing point of such 
water is _________ ×10
-3°
C. 
Atomic mass of C,H and O are 12,1 and 16 a.m.u. respectively. 
[Given : Molal depression constant and density of water 
are    1.86 K kg mol
-1
 and   1 g cm
-3
 respectively.] 
 
JEE Main 2023 (Online) 1st February Evening Shift 
Q.12. 25 mL of an aqueous solution of KCl was found to require 20 
mL of 1 M AgNO3 solution when titrated using K2CrO4 as an 
indicator. What is the depression in freezing point of KCl solution 
of the given concentration? _________ (Nearest integer). 
(Given :    Kf=2.0 K kg mol
-1
) 
Assume 1) 100% ionization and 2) density of the aqueous 
solution as 1 g mL
-1
 
 
JEE Main 2023 (Online) 1st February Morning Shift 
Q.13. At 27°C, a solution containing  2.5 g of solute in  250.0 mL of 
solution exerts an osmotic pressure of  400 Pa. The molar mass of 
the solute is ___________  g mol
-1
 (Nearest integer) 
(Given :     R=0.083 L bar K
-1
 mol
-1
) 
 
JEE Main 2023 (Online) 31st January Morning Shift 
Q.14. Lead storage battery contains 38% by weight solution 
of H2SO4. The van't Hoff factor is 2.67 at this concentration. The 
temperature in Kelvin at which the solution in the battery will 
freeze is ________. (Nearest integer). 
 
 
JEE Main 2023 (Online) 30th January Evening Shift 
 
Q.15. A solution containing  2 g of a non-volatile solute in  20 g of 
water boils at  373.52 K. The molecular mass of the solute is 
___________  g mol-1. (Nearest integer) 
Given, water boils at     
 
JEE Main 2023 (Online) 30th January Morning Shift 
Q.16. The number of pairs of the solutions having the same value 
of the osmotic pressure from the following is _________. 
(Assume 100% ionization) 
 
JEE Main 2023 (Online) 25th January Evening Shift 
 
Q.17. The osmotic pressure of solutions of PVC in cyclohexanone 
at 300 K are plotted on the graph. 
The molar mass of PVC is ____________ g mol-1 (Nearest integer) 
 
 
JEE Main 2023 (Online) 25th January Morning Shift 
 
Q.18. The total pressure observed by mixing two liquids A and B 
is 350 mm Hg when their mole fractions are 0.7 and 0.3 
respectively.