 # MCQ on Gas Laws – Behavior of Gas – Boyle’s Law, Charles’s Law Avogadro’s Law

## MCQ on gas laws

MCQ General Knowledge on Behavior of Gas Boyle’s Law, Charles’s Law Avogadro’s Law Objective short Questions and Answers for class 9 10 and aspirants who are preparing for competitive govt job examinations like SSC, CGL, MTS, IAS, UPSC, Railway, Banking, Defence, Police CDS, etc..

[MCQ.1] The constant quantity of Boyle’s Law is

A: Only mass of the gas
B: Only temperature of a gas
C: Mass and Pressure of a gas
D: Mass and temperature of a gas

D: Mass and temperature of a gas.

[MCQ.2] Let the pressure P and volume V for a certain gas. If the pressure is increased by 25% at a constant temperature, then what would be the volume of the gas?

A: 0.6V
B: 0.75V
C: 0.8V
D: 0.85V

0.8V

[MCQ.3] What is the nature of the pressure-volume (P-V) graph in Boyle’s Law?

A: Straight Line;
B: Circle:
C: Elliptical;
D: Rectangular Hyperbola:

Rectangular Hyperbola.

[MCQ.4] What is the nature of the pressure-volume vs Pressure (PV vs P) graph in Boyle’s Law?

A: Straight Line parallel to P axis;
B: Straight line parallel to PV axis:
C: Elliptical;
D: Hyperbola:

Straight-line parallel to the P axis.

[MCQ.5] The unit of pressure in the SI system is-

A: N
B: N-m
C: N-m2
D: N/m2

N/m2

[MCQ.6] 1 m3 = ______ cm3

A: 100
B: 103
C:105
D: 106

D: 106

[MCQ.7] If the pressure of a certain amount of gas is reduced to 1/4th of its initial pressure at a fixed temperature, then what would be its final volume?

A: 2 times
B: 3 times
C: 4 times
D: 6 times

C: 4 times

[MCQ.8] If the pressure is increased by 2 times of a certain amount of gas at a fixed temperature, then what would be its final volume?

A: Double
B: One half
C: Tripple
D: One fourth

B: One half

[MCQ.9] Suppose, at for a gas having constant mass the volume is V0 at temperature 0 oC. What would be its final volume at 100 oC if the pressure remains constant?

A: (293/273)V0
B:(283/273)V0
C: (303/273)V0
D: (373/273)V0

(303/273)V0

[MCQ.10] For a given mass of an ideal gas at constant pressure, the graph V – t (t in Celcius scale), intersect the temperature axis at –

A: – 273 oC
B: 0 oC
C: 273 oC
D: Do not intersect.

A: – 273 oC

[MCQ.11] In which scale of temperature, the temperature can not be negative?

A: Celcius Scale
B: Fernheight Scale
C: Absolute Scale
D: All of the above

C: Absolute Scale

[MCQ.12] The Freezing point of water in absolute scale is-

A: 0 K
B: 273 K
C: 212 K
D: None of the above;

B: 273 K

[MCQ.13] If the temperature is increased from 0 oC to 30 oC at a constant pressure of gas having fixed mass, then the ratio of initial and final volume will be –

A: 91 : 101
B: 91 : 100
C: 91 : 111
D: 91 : 121

A: 91 : 101

[MCQ.14] The constant quantity(s) in Charle’s Law is (are)-

A: Temperature
B: Volume
C: Pressure and Mass of gas
D: Temperature and Mass of gas

Pressure and Mass of a gas.

[MCQ.15] The nature of the V-t (t in Celsius scale) graph in Charle’s law is-

A: Straight line
B: Circle
C: Parabola
D: Hyperbola

Straight line

[MCQ.16] At which temperature the volume of gas reduces to Zero?

A: 0 K
B: 0 oC
C: 273 oC
D: 273 K

A: 0 K

[MCQ.17] Which Scientist discovered the absolute scale of temperature?

A: Charles
B: Boyle
C: Kelvin
D: Gay-Lussac.

Kelvin

[MCQ.18] At which temperature the real gas behaves as an ideal gas?

A: At high pressure and low temperature;
B: At low-pressure and high temperature;
C: At low pressure and low temperature;
D: AT high pressure and high temperature;

B: At high temperature and low pressure;

[MCQ.19] The molar mass of water is –

A: 16 g
B: 20 g
C: 18 g
D: 44 g

C: 18 g

[MCQ.20] The mass of 5 mol of Hydrogen gas is-

A: 5 g
B: 10 g
C: 18 g
D: 27 g

B: 10 g

[MCQ.21] In the case of collision of two gas molecule of an ideal gas –

A: The linear momentum is conserved only;
B: The kinetic energy is conserved only;
C: Linear momentum and kinetic energy both conserve;
D: Linear momentum and kinetic energy both are not conserved;

C: Linear momentum and kinetic energy both are conserved.

[MCQ.22] The energy of the molecules of an ideal gas is –

A: Only potential energy;
B: Only kinetic energy;
C: Kinetic energy + potential energy;
D: Kinetic energy – potential energy;

B: Only kinetic energy;

[MCQ.23] Which is the Ideal Gas Equation from the following?

A: PV = mc2;
B: PV = mgh;
C: PV = nRT;
D: PV = mSt;

C: PV = nRT;

[MCQ.24] Which is the constant quantity in Ideal Gas Equation?

A: Pressure P
B: Volume V
C: R
D: Temperature

C: R

[MCQ.25] The value of Universal Gas Constant in CGS unit is –

A: 8.31 * 106
B: 8.31 * 107
C: 8.31 * 108
D: 8.31 * 109

B: B: 8.31 * 107

[MCQ.26] The dimension of the universal gas constant is –

A: M L2 T-1 N-1
B: M L-1 T-1 N-2K-1
C: M L2 T-1 N-2 K
D: M L-1 T-2 N-1 K-1

D: M L-1 T-2 N-1 K-1

[MCQ.27] According to the kinetic theory of gas, at which temperature the kinetic energy of a molecule of an ideal gas becomes zero?

A: — 273 oC
B: 0 oC
C: – 100 oC
D: 273 K

A: — 273 oC

[MCQ.28] 84 g of N2 = ______ g N2.

A: 1 g
B: 2 g
C: 3 g
D: 4 g

C: 3 g

[MCQ.29] Which of the following has the largest volume?
2 g of Hydrogen Gas, 28 g of Nitrogen Gas, 44 g of CO2 gas.

A: 2 g of Hydrogen Gas
B: 28 g of Nitrogen Gas
C: 44 g of CO2 gas
D: All gasses have the same volume.

D: All the gas has the same volume.

[MCQ.30] How many atoms are there in 1 mol of CO2 gas if the Avogadro number in N?

A: N
B: 2N
C: 3N
D: 4N

C: 3N

[MCQ.31] If the mass of 11.2 L of CO2 is 22g, then what is its atomic mass?

A: 22
B: 44:
C: 88
D: 11

B: 44

[MCQ.32] The mass of an O2 molecule is –

A: 5.31 * 10-23g
B: 10.62 * 10-23
C: 15.93 * 10-23
D: 2.65 * 10-23

5.31 * 10-23g

[MCQ.33] The number of molecules of 7g of N2 gas is-

A: 22.044 * 1023
B: 1.506 * 1023
C: 3.011 * 1023
D: 6.022 * 1023

1.506 * 1023

[MCQ.34] The volume of 2.2 g CO2 at 27 oC and 570 mm pressure is –

A: 4.83 L
B: 0.82 L
C: 3.82 L
D: 1.64 L

D: 1.64 L

[MCQ.35] At which condition the real gas deviated from the ideal gas?

A: At low temperature and low pressure
B: At Low pressure and high temperature;
C: At high pressure and low temperature;
D: At high pressure and high temperature;

At low temperature and high pressure.

[MCQ.36] The state of the equation for 7g of Oxygen gas is _

A: PV = 7RT
B: PV = (32/7)RT
C: PV = (7/32)RT
D: PV = 32RT

C: PV = (7/32)RT

[MCQ.37]If the pressure of a certain amount of gas is increased at a constant temperature, the density of the gas is –

A: Remain Constant;
B: Decreased;
C: Increased;
D: Can not be determined;

Increased

[MCQ.38] What would be the volume of 22g of Carbon dioxide at STP?

A: 11.2 L
B: 1.12 L
C: 22.4 L
D: 2.24 L

11.2 L

[MCQ.39] The molar volume of any gas at STP is –

A: 22.4 L
B: 2.24 L
C: 44 L
D: 24.2 L