Kinetic Theory of Gases: JEE Main Previous Year Questions (2021-2026)

 Page 1


2024 
 
Q1 - 2024 (01 Feb Shift 1) 
Two moles a monoatomic gas is mixed with six moles of a diatomic gas. The molar 
specific heat of the mixture at constant volume is : 
(1) 
9
4
R 
(2) 
7
4
R 
(3) 
3
2
?? 
(4) 
5
2
?? 
Q2 - 2024 (01 Feb Shift 2) 
If the root mean square velocity of hydrogen molecule at a given temperature and 
pressure is 2 km/s, the root mean square velocity of oxygen at the same condition in 
km/s is : 
(1) 2.0 
(2) 0.5 
(3) 1.5 
(4) 1.0 
Q3 - 2024 (27 Jan Shift 1) 
The average kinetic energy of a monatomic molecule is 0.414eV at temperature : 
(Use ?? ?? = 1.38 × 10
-23
 J/mol - K ) 
(1) 3000 K 
(2) 3200 K 
(3) 1600 K 
(4) 1500 K 
 
Page 2


2024 
 
Q1 - 2024 (01 Feb Shift 1) 
Two moles a monoatomic gas is mixed with six moles of a diatomic gas. The molar 
specific heat of the mixture at constant volume is : 
(1) 
9
4
R 
(2) 
7
4
R 
(3) 
3
2
?? 
(4) 
5
2
?? 
Q2 - 2024 (01 Feb Shift 2) 
If the root mean square velocity of hydrogen molecule at a given temperature and 
pressure is 2 km/s, the root mean square velocity of oxygen at the same condition in 
km/s is : 
(1) 2.0 
(2) 0.5 
(3) 1.5 
(4) 1.0 
Q3 - 2024 (27 Jan Shift 1) 
The average kinetic energy of a monatomic molecule is 0.414eV at temperature : 
(Use ?? ?? = 1.38 × 10
-23
 J/mol - K ) 
(1) 3000 K 
(2) 3200 K 
(3) 1600 K 
(4) 1500 K 
 
Q4 - 2024 (27 Jan Shift 2) 
The total kinetic energy of 1 mole of oxygen at 27
°
C is : 
[Use universal gas constant (R) = 8.31 J/moleK ] 
(1) 6845.5 J 
(2) 5942.0 J 
(3) 6232.5 J 
(4) 5670.5 J 
Q5 - 2024 (29 Jan Shift 1) 
Two vessels A and B are of the same size and are at same temperature. A contains 1 g 
of hydrogen and ?? contains 1 g of oxygen. P
A
 and P
B
 are the pressures of the gases in A 
and B respectively, then 
?? ?? ?? ?? is : 
(1) 16 
(2) 8 
(3) 4 
(4) 32 
Q6 - 2024 (29 Jan Shift 2) 
The temperature of a gas having 2.0 × 10
25
 molecules per cubic meter at 1.38 atm 
(Given, k = 1.38 × 10
-23
JK
-1
) is : 
(1) 500 K 
(2) 200 K 
(3) 100 K 
(4) 300 K 
Q7 - 2024 (29 Jan Shift 2) 
N moles of a polyatomic gas (f = 6) must be mixed with two moles of a monoatomic gas 
so that the mixture behaves as a diatomic gas. The value of N is : 
(1) 6 
(2) 3 
Page 3


2024 
 
Q1 - 2024 (01 Feb Shift 1) 
Two moles a monoatomic gas is mixed with six moles of a diatomic gas. The molar 
specific heat of the mixture at constant volume is : 
(1) 
9
4
R 
(2) 
7
4
R 
(3) 
3
2
?? 
(4) 
5
2
?? 
Q2 - 2024 (01 Feb Shift 2) 
If the root mean square velocity of hydrogen molecule at a given temperature and 
pressure is 2 km/s, the root mean square velocity of oxygen at the same condition in 
km/s is : 
(1) 2.0 
(2) 0.5 
(3) 1.5 
(4) 1.0 
Q3 - 2024 (27 Jan Shift 1) 
The average kinetic energy of a monatomic molecule is 0.414eV at temperature : 
(Use ?? ?? = 1.38 × 10
-23
 J/mol - K ) 
(1) 3000 K 
(2) 3200 K 
(3) 1600 K 
(4) 1500 K 
 
Q4 - 2024 (27 Jan Shift 2) 
The total kinetic energy of 1 mole of oxygen at 27
°
C is : 
[Use universal gas constant (R) = 8.31 J/moleK ] 
(1) 6845.5 J 
(2) 5942.0 J 
(3) 6232.5 J 
(4) 5670.5 J 
Q5 - 2024 (29 Jan Shift 1) 
Two vessels A and B are of the same size and are at same temperature. A contains 1 g 
of hydrogen and ?? contains 1 g of oxygen. P
A
 and P
B
 are the pressures of the gases in A 
and B respectively, then 
?? ?? ?? ?? is : 
(1) 16 
(2) 8 
(3) 4 
(4) 32 
Q6 - 2024 (29 Jan Shift 2) 
The temperature of a gas having 2.0 × 10
25
 molecules per cubic meter at 1.38 atm 
(Given, k = 1.38 × 10
-23
JK
-1
) is : 
(1) 500 K 
(2) 200 K 
(3) 100 K 
(4) 300 K 
Q7 - 2024 (29 Jan Shift 2) 
N moles of a polyatomic gas (f = 6) must be mixed with two moles of a monoatomic gas 
so that the mixture behaves as a diatomic gas. The value of N is : 
(1) 6 
(2) 3 
(3) 4 
(4) 2 
Q8 - 2024 (30 Jan Shift 1) 
Two thermodynamical process are shown in the figure. The molar heat capacity for 
process A and ?? are ?? ?? and ?? ?? . The molar heat capacity at constant pressure and 
constant volume are represented by ?? ?? and ?? ?? , respectively. Choose the correct 
statement. 
 
[We changed options. In official NTA paper no option was correct.] 
(1) ?? ?? = 8, ?? ?? = 0 
(2) ?? ?? = 0 and ?? ?? = 8 
(3) ?? ?? > ?? ?? > ?? ?? > ?? ?? 
(4) ?? ?? > ?? ?? > ?? ?? 
Q9 - 2024 (30 Jan Shift 1) 
At which temperature the r.m.s. velocity of a hydrogen molecule equal to that of an 
oxygen molecule at 47
°
C ? 
(1) 80 K 
(2) -73 K 
(3) 4 K 
(4) 20 K 
 
Page 4


2024 
 
Q1 - 2024 (01 Feb Shift 1) 
Two moles a monoatomic gas is mixed with six moles of a diatomic gas. The molar 
specific heat of the mixture at constant volume is : 
(1) 
9
4
R 
(2) 
7
4
R 
(3) 
3
2
?? 
(4) 
5
2
?? 
Q2 - 2024 (01 Feb Shift 2) 
If the root mean square velocity of hydrogen molecule at a given temperature and 
pressure is 2 km/s, the root mean square velocity of oxygen at the same condition in 
km/s is : 
(1) 2.0 
(2) 0.5 
(3) 1.5 
(4) 1.0 
Q3 - 2024 (27 Jan Shift 1) 
The average kinetic energy of a monatomic molecule is 0.414eV at temperature : 
(Use ?? ?? = 1.38 × 10
-23
 J/mol - K ) 
(1) 3000 K 
(2) 3200 K 
(3) 1600 K 
(4) 1500 K 
 
Q4 - 2024 (27 Jan Shift 2) 
The total kinetic energy of 1 mole of oxygen at 27
°
C is : 
[Use universal gas constant (R) = 8.31 J/moleK ] 
(1) 6845.5 J 
(2) 5942.0 J 
(3) 6232.5 J 
(4) 5670.5 J 
Q5 - 2024 (29 Jan Shift 1) 
Two vessels A and B are of the same size and are at same temperature. A contains 1 g 
of hydrogen and ?? contains 1 g of oxygen. P
A
 and P
B
 are the pressures of the gases in A 
and B respectively, then 
?? ?? ?? ?? is : 
(1) 16 
(2) 8 
(3) 4 
(4) 32 
Q6 - 2024 (29 Jan Shift 2) 
The temperature of a gas having 2.0 × 10
25
 molecules per cubic meter at 1.38 atm 
(Given, k = 1.38 × 10
-23
JK
-1
) is : 
(1) 500 K 
(2) 200 K 
(3) 100 K 
(4) 300 K 
Q7 - 2024 (29 Jan Shift 2) 
N moles of a polyatomic gas (f = 6) must be mixed with two moles of a monoatomic gas 
so that the mixture behaves as a diatomic gas. The value of N is : 
(1) 6 
(2) 3 
(3) 4 
(4) 2 
Q8 - 2024 (30 Jan Shift 1) 
Two thermodynamical process are shown in the figure. The molar heat capacity for 
process A and ?? are ?? ?? and ?? ?? . The molar heat capacity at constant pressure and 
constant volume are represented by ?? ?? and ?? ?? , respectively. Choose the correct 
statement. 
 
[We changed options. In official NTA paper no option was correct.] 
(1) ?? ?? = 8, ?? ?? = 0 
(2) ?? ?? = 0 and ?? ?? = 8 
(3) ?? ?? > ?? ?? > ?? ?? > ?? ?? 
(4) ?? ?? > ?? ?? > ?? ?? 
Q9 - 2024 (30 Jan Shift 1) 
At which temperature the r.m.s. velocity of a hydrogen molecule equal to that of an 
oxygen molecule at 47
°
C ? 
(1) 80 K 
(2) -73 K 
(3) 4 K 
(4) 20 K 
 
Q10 - 2024 (30 Jan Shift 2) 
If three moles of monoatomic gas (?? =
5
3
) is mixed with two moles of a diatomic gas 
(?? =
7
5
), the value of adiabatic exponent ?? for the mixture is: 
(1) 1.75 
(2) 1.40 
(3) 1.52 
(4) 1.35 
Q11 - 2024 (31 Jan Shift 1) 
The parameter that remains the same for molecules of all gases at a given temperature 
is : 
(1) kinetic energy 
(2) momentum 
(3) mass 
(4) speed 
Q12 - 2024 (31 Jan Shift 2) 
A gas mixture consists of 8 moles of argon and 6 moles of oxygen at temperature T. 
Neglecting all vibrational modes, the total internal energy of the system is 
(1) 29RT 
(2) 20RT 
(3) 27RT 
(4) 21RT 
 
 
 
Page 5


2024 
 
Q1 - 2024 (01 Feb Shift 1) 
Two moles a monoatomic gas is mixed with six moles of a diatomic gas. The molar 
specific heat of the mixture at constant volume is : 
(1) 
9
4
R 
(2) 
7
4
R 
(3) 
3
2
?? 
(4) 
5
2
?? 
Q2 - 2024 (01 Feb Shift 2) 
If the root mean square velocity of hydrogen molecule at a given temperature and 
pressure is 2 km/s, the root mean square velocity of oxygen at the same condition in 
km/s is : 
(1) 2.0 
(2) 0.5 
(3) 1.5 
(4) 1.0 
Q3 - 2024 (27 Jan Shift 1) 
The average kinetic energy of a monatomic molecule is 0.414eV at temperature : 
(Use ?? ?? = 1.38 × 10
-23
 J/mol - K ) 
(1) 3000 K 
(2) 3200 K 
(3) 1600 K 
(4) 1500 K 
 
Q4 - 2024 (27 Jan Shift 2) 
The total kinetic energy of 1 mole of oxygen at 27
°
C is : 
[Use universal gas constant (R) = 8.31 J/moleK ] 
(1) 6845.5 J 
(2) 5942.0 J 
(3) 6232.5 J 
(4) 5670.5 J 
Q5 - 2024 (29 Jan Shift 1) 
Two vessels A and B are of the same size and are at same temperature. A contains 1 g 
of hydrogen and ?? contains 1 g of oxygen. P
A
 and P
B
 are the pressures of the gases in A 
and B respectively, then 
?? ?? ?? ?? is : 
(1) 16 
(2) 8 
(3) 4 
(4) 32 
Q6 - 2024 (29 Jan Shift 2) 
The temperature of a gas having 2.0 × 10
25
 molecules per cubic meter at 1.38 atm 
(Given, k = 1.38 × 10
-23
JK
-1
) is : 
(1) 500 K 
(2) 200 K 
(3) 100 K 
(4) 300 K 
Q7 - 2024 (29 Jan Shift 2) 
N moles of a polyatomic gas (f = 6) must be mixed with two moles of a monoatomic gas 
so that the mixture behaves as a diatomic gas. The value of N is : 
(1) 6 
(2) 3 
(3) 4 
(4) 2 
Q8 - 2024 (30 Jan Shift 1) 
Two thermodynamical process are shown in the figure. The molar heat capacity for 
process A and ?? are ?? ?? and ?? ?? . The molar heat capacity at constant pressure and 
constant volume are represented by ?? ?? and ?? ?? , respectively. Choose the correct 
statement. 
 
[We changed options. In official NTA paper no option was correct.] 
(1) ?? ?? = 8, ?? ?? = 0 
(2) ?? ?? = 0 and ?? ?? = 8 
(3) ?? ?? > ?? ?? > ?? ?? > ?? ?? 
(4) ?? ?? > ?? ?? > ?? ?? 
Q9 - 2024 (30 Jan Shift 1) 
At which temperature the r.m.s. velocity of a hydrogen molecule equal to that of an 
oxygen molecule at 47
°
C ? 
(1) 80 K 
(2) -73 K 
(3) 4 K 
(4) 20 K 
 
Q10 - 2024 (30 Jan Shift 2) 
If three moles of monoatomic gas (?? =
5
3
) is mixed with two moles of a diatomic gas 
(?? =
7
5
), the value of adiabatic exponent ?? for the mixture is: 
(1) 1.75 
(2) 1.40 
(3) 1.52 
(4) 1.35 
Q11 - 2024 (31 Jan Shift 1) 
The parameter that remains the same for molecules of all gases at a given temperature 
is : 
(1) kinetic energy 
(2) momentum 
(3) mass 
(4) speed 
Q12 - 2024 (31 Jan Shift 2) 
A gas mixture consists of 8 moles of argon and 6 moles of oxygen at temperature T. 
Neglecting all vibrational modes, the total internal energy of the system is 
(1) 29RT 
(2) 20RT 
(3) 27RT 
(4) 21RT 
 
 
 
Answer Key 
Q1 (1)  Q2 (2) Q3 (2)  Q4 (3) 
Q5 (1)  Q6 (1) Q7 (3)  Q8 (3) 
Q9 (4)  Q10 (3) Q11 (1) Q12 (3) 
 
Solutions 
Q1 
?? ?? =
?? 1
?? ?? 1
+ ?? 2
?? ?? 2
?? 1
+ ?? 2
 =
2 ×
3
2
?? + 6 ×
5
2
?? 2 + 6
 =
9
4
?? 
Q2 
V
rms
=
v
3RT
M
 
V
1
 V
2
= v
M
2
M
1
?
2
 V
2
=
v
32
2
 
V
2
= 0.5 km/s 
Q3 
For monoatomic molecule degree of freedom = 3. 
? K
avg
=
3
2
 K
B
T 
T =
0.414 × 1.6 × 10
-19
× 2
3 × 1.38 × 10
-23
 
= 3200 K 
Q4 
Kinetic energy =
f
2
nRT