# WBBSE Class 10 Physical Science MCQ Questions Chapter 2 Behaviour of Gases

Well structured WBBSE Class 10 Physical Science MCQ Questions Chapter 2 Behaviour of Gases can serve as a valuable review tool before exams.

## Behaviour of Gases Class 10 WBBSE MCQ Questions

Multiple Choice Questions (MCQ) :

Question 1.
For liquefaction of gas, the favourable conditions are :
A. low temperature and low pressure
(B) low temperature and a catalyst
(C) low temperature and high pressure
(D) low temperature, high pressure and a catalyst.
(B) Low temperature and high pressure

Question 2.
The critical temperature of a gas is the temperature :
(A) below which it cannot be liquefied
(B) at which it solidifies
(C) above which it cannot be liquefied
(D) above which it can no longer remain in the gaseous state.
(D) Above which it cannot be liquefied

Question 3.
P,V,T stand for pressure, volume and temperature of a gas. Which of the following will expres Boyle’s law?
(A) V × T when P is constant
(B) V × $$\frac{1}{P}$$ when T is constant
(C) PV=RT
(D) PV = n RT
(B) V × $$\frac{1}{P}$$ when T is constant

Question 4.
Gases often deviate from the ideal gas behaviour becape their molecules:
(A) posses negligible volume
(B) are polyatomic
C. have forces of attraction between them
(D) are not attracted to one another
(C) Have forces of attraction between them

Question 5.
One of the following is not the postulate of the kinetic theory of gases :
(A) the actual volume of the molecules is negligible compared to the volume of the gas
(B) the molecules remain in ceaseless motion
C there are sufficient attractive forces between the molecules
(D) the average kinetic energy of the gas molecules is directly proportional to the absolute temperature.
(C) There are sufficient attractive forces between the molecules.

Question 6.
Which of the following is valid at absolute zero?
(A) Kinetic energy of the gas becomes zero, but the molecular motion does not become zero
(B) Kinetic energy of the gas becomes zero and the molecular motion also becomes zero,
(C) Kinetic energy of the gas decreases but does not become zero
(D) None of the above.
(D) None of the above

Question 7.
The pressure of real gases is less than the pressure of an ideal gas because of :
(A) increase in the number of collisions
(B) finite size of the molecules
(C) increase in kinetic energy
(D) intermolecular forces?
(D) Intermolecular forces.

Question 8.
The temperature at which a real gas obeys the ideal gas laws over an appreciable pressure range is called the :
(A) critical temperature
(B) inversion temperature
(C) transition temperature
(D) Boyle’s temperature
(D) Boyle’s temperature

Question 9.
Attractive forces and size effects in a gas can be neglected at:
(A) low temperature
(B) high pressure
(C) low pressures and high temperatures
(D) low temperatures and high pressures
(C) Low pressures and high temperatures

Question 10.
An ideal gas le one which:
(A) obeys gas laws
(B) obeys Boyle’s law
(C) obeys Charle’s law
(A) obeys gas laws

Question 11.
The volume of any gas at this temperature becomes zero :
(A) +273° C
(B) -273° C
(C) 273 K
(D) -273 K
(B) -273° C

Question 12.
Pressure cooker reduces cooking time because :
(A) the heat is more easily distributed
(B) the higher pressure tenderizes the food
(C) the boiling point of water inside is elevated
(D) a large flame is used
(C) the boiling point of water inside is elevated

Question 13.
In the ideal gas equation PV = nRT, the value of R depends upon:
(A) unit of measurement
(B) temperature of gas
(C) pressure of gas
(D) nature of gas
(A) unit of measurement

Question 14.
At constant mass and constant volume, the relation between pressure and temperature is :
(A) Boyle’s law
(B) Charle’s law
(C) Gay Lussac’s law
(D) None of these.
(C) Gay Lussac’s law

Question 15.
At constant mass and constant temperature the relation between volume and pressure is :
(A) Charle’s law
(B) Boyle’s law
(C) Gay Lussac’s law
(D) None of these.
(B) Boyle s law

Question 16.
The value of absolute temperature in celsius scale is :
(A) 0° C
(B) -100° C
(C) -273° C
(D) -373° C
(C) -273° C

Question 17.
The boiling point of water in Kelvin scale is :
(A) 0 K
(B) 373 K
(C) 100 K
(D) 273 K
(B) 373 K

Question 18.
What will be the value of 127° C in Kelvin scale?
(A) 127 K
(B) 400 K
(C) 146 K
(D) 200 K
(B) 400 K

Question 19.
The relation between 100° C and 373 K is
(A) 100° C > 373 K
(B) 100° C < 373 K
(C) 100° C = 373 K
(D) Non of these.
(C) 100° C = 373 K

Question 20.
At NTP, if the volume of any gas is 10 lit then at 27° C and 750 mm pressure what will be its volume :
(A) 11.1 lit
(B) 15 lit
(C) 8.1 lit
(D) 8.2 lit
(A) 11.1 lit

Question 21.
A gas having temperature 0° C is heated so that its pressure and volume are doubled. What will be the final temperature of the gas?
(A) 1092 K
(B) 1002 K
(C) 999 K
(D) 980 K
(A) 1092 K

Question 22.
The relation between celsius and absolute scale is :
(A) T = t + 273
(B) T = t – 273
(C) t = T + 273
(D) t = T – 273
(A) T = t + 273

Question 23.
Normal pressure is :
(A) 1.013 × 106 dyne / cm2
(B) 2.013 × 106 dyne / cm2
(C) 1.05 × 106 dyne / cm2
(D) 1.09 × 106 dyne / cm2
(A) 1.013 × 106 dyne cm2

Question 24.
P1 V1 = P2 V2 is related to :
(A) Boyle’s law
(B) Charle’s law
(C) Regnault’s law
(D) None of these
(A) Boyle s law

Question 25.
The relation between pressure, temperature and density of a gas is:
(A) $$\frac{P}{DT}$$ = constant
(B) $$\frac{P}{DT}$$ = constant
(C) $$\frac{PD}{T}$$ = constant
(D) None of these
(B) $$\frac{P}{DT}$$ = constant

Question 26.
Volume of 4.4 g of CO2 at STP is :
(A) 22.4 L
(B) 2.24 L
(C) 224 L
(D) 44.8 L
(A) 2.24 L

Question 27.
Gas deviates from ideal gas nature because molecules.
(A) are colourless
(B) attract each other
(C) contain covalent bond
(D) show Brownian movement
(B) attract each other

Question 28.
A gas will approach ideal behaviour at :
(A) low temperature and low pressure
(B) low temperature and high pressure
(C) high temperature and low pressure
(D) high temperature and high pressure.
(C) high temperature and low pressure

Question 29.
Kinetic theory of gases proves :
(A) only Boyle’s law
(B) only Charle’s law
(D) all of these
(D) all of these

Question 30.
The unit of p v in the equation Pv = nRT is
(A) N / m
(B) N.m
(C) N / m2
(D) N-m2
(B) N.m

Question 31.
Which of the following order is corect?
(A) 0 K > 0° F > 0° C
(B) 0 K < 0° F < 0° C (C) 0°C > 0° F > 0 K
(D) 0 K = 0° F = 0° C
(B) 0 K < 0° F < 0° C

Question 32.
All the temperature are positive when expressed in
(A) Celsius scale
(B) Fahreuheit scale
(C) Kelvin scale
(D) None of these
(C) Kelvin scale

Question 33.
Real gas behaviour differs from ideal gas behaviour because the molecules of real gases
(A) attract one another
(B) collide
(C) have mass
(D) are arranged in a regular geometric pattern
(A) attract one another

Question 34.
Collisions of Helium atoms with the walls of a closed container cause :
(A) condensation
(B) decrease in volume
(C) gas pressure
(D) an overall loss of energy
(C) gas pressure

Question 35.
Which is the correct relationship between centigrade and Kelvin scale?
(A) T = t + 273
(B) $$\frac{T}{5}$$ = $$\frac{t-32}{9}$$
(C) T = t – 273
(D) t = T + 273
(A) T = t + 273

Question 36.
If the pressure of any gas be increased keeping its temperature and mass constant, then its density will :
(A) increase
(B) decrease
(C) remain same
(D) depend upon other factors
(A) increase

Question 37.
A real gas behaves as an ideal gas :
(A) at very low pressure and very low temperature
B) at very low pressure and very high temperature
(C) at very high pressure and very low temperature
(D) at very high pressure and very high temperature
(B) at very low pressure and very high temperature

Question 38.
Volume-temperature relationship was given by
(A) Boyle
(B) Charles
(D) Gay Lussac
(B) Charles

Question 39.
At a fixed temperature and pressure, the average distance between molecules would be greatest in a sample of :
(A) air
(B) water
(C) wood
(D) diamond
(A) air

Question 40.
Unit of molar mass of a gas is :
(A) gram
(B) gram / cm3
(C) g / mol
(D) mol
(C) g / mol

Question 41.
Which of the following plots is not linear for an ideal gas ?
(A) P-T
(B) V-T
(C) P-V
(D) P-d
(C) P-V

Fill in the blanks :

1. According to kinetic theory of gases, a gas consists of discrete particles called ________.
molecules

2. The scale of temperature with -273°C as zero is called ________.
Absolute or Kelvin temperature scale

3. Real gases do not behave like ideal gases because they have inter molecular ________ and the molecules do not have negligible volume.
attraction

4. The law which describes the relationship between the volume and temperature of a gas at constant pressure is called ________.
Charle’s law

5. According to the kinetic theory of gases, the kinetic energy of gases is directly proportional to its ________.
absolute or Kelvin temperature

6. The volume of a gas is zero at ________ temperature.
absolute

7. At constant temperature for a given volume of gas the product of its pressure and its volume is ________.
constant

8. The value of absolute zero is ________ on Celsius scale.
-273°C

9. The equation of ideal gas for n gram-moles is ________.
P V=n R T

10. The volume of a given mass of gas varies directly as ________ temperature at constant pressure.
absolute

11. Gases like H2, O2, N2, Cl2 etc. which obey Boyle’s law and Charle’s law at low pressure and ________ temperature are called real gases.
high

12. The constant quantities in Boyle’s law are ________ and temperature.
mass

13. Gaseous molecules have no mutual force of ________, so they are always in an incessant motion.
atrraction

14. If heat is supplied to a gas, its molecules move with more ________, so temperature of the gas rises.
energy

15. The normal temperature is taken as 0°C or ________ K and the normal pressure is taken as 76 cm mercury or 1 atmosphere.
273

16. At constant temperature, the volume of a given mass of gas varies ________ as its pressure.
inversely

17. For a given mass of a gas or vapour at a constant temperature, pressure × _______ = constant.
volume

18. The boiling point of water is ________ Kelvin.
273

19. At ________ °C, the gas molecules become motionless.
(-) 273

20. 330 K = _______ ° C
57

21. The pressure of a gas is determined by ________.
Manometer

22. The value of normal pressure in SI system is ________ pascal.
1.013 × 105

273

24. Law of pressure is known as ________.
Regnault’s law

25. Any real gas becomes ________ before it reaches to absolute zero.
liquefied

26. Equal volumes of two gases under similar conditions of temperature contain ________ number of molecules.
same

27. The volume of gas is zero at ________ temperature.
absolute

28. At constant temperature for a given volume of gas the product of its pressure and its volume is ________.
constant.

29. The velocities of molecules ________ with rise of temperature.
increase.

30. The equation of ideal gas for n gram-moles is ________.
PV = nRT

31. Zero reading of the kelvin scale is known as ________ zero.
absolute

32. The temperature above which a gas behaves like and ideal gas is called ________ temperature.
Boyles

33. Value of R in Ltt-atm mol-1 k-1 unit is ________.
0.082

34. The number of molecules present in a gram molecule mass of a substance is called ________.

35. Molar volume of an ideal gas is ________ ML at N.T.P.
22400

36. Density of moist air is ________ than that of dry air.
less

37. At a fixed temperature, if the pressure of the gas is doubled, volume of the gas is ________.
halved

38. PV versus P curve of an ideal gas gives a straight line parallel to ________ axis.
X

39. Under similar condition of temperature and pressure, equal volumes of all gases contain same number of ________.
molecules

40. R is called gas ________ constant.
universal

State whether the following statement is True or False : VSA

1. Freezing polnt of water in absolute scale is 290 K.
False

2. Gases show deviations from ideal behaviour at high temperatures and high pressures.
False

3. The value of Avogadro Number is 6.022 × 1023
True

4. Unit of R in litre atmosphere per kelvin per mole.
True

5. The N.T.P is 25° c and 1 atm. pressure.
False

6. P versus 1 / v curve gives a straight line.
True

7. The lowest temperature of this universe is O K.
True

8. The slope of V versus T curve at higher pressure is steeper.
False

9. According to kinetic theory of gases, intermolecular attractive force exists between gas molecules.
False

10. Volume of a gas is actually the volume of the container in which the gas is kept.
True

11. At Constant pressure, as the temperature increases, the volume of the gas also increases.
True

12. The rate of diffusion of methane is more than that of Sulphur dioxide.