1. Equal masses of methane and oxygen are mixed in an empty container at 25°C. The fraction of the total pressure exerted by oxygen is
2. In van der waals equation of state of the gas law, the constant b is a measure of
1) inter molecular repulisons 2) intermolecular attraction
3) volume occupied by the molecules
4) intermolecular collisions per unit volume
3. For an ideal gas, number of moles per litre in terms of its pressure P, gas constant R and temperature T is
4. 0.5 moles of gas A and X moles of B exert a pressure of 200 pa in a container of volume 10 m3 at 1000 K. Given R is the gas constant in JK−1mol−1 m, X is ..
5. The initial volume of a gas cylinder is 750 ml. If the pressure of gas inside the cylinder changes from 840 mm Hg to 360 mm Hg. The final volume of the gas will be
1) 1.750 l 2) 7.50 l 3) 3.60 l 4) 4.032 l
6. For real gases van der waals equation is
a and b are van der waals constants. Two sets of gases are
i) O2, CO2, H2 and He ii) CH4, O2 and H2 The gases given in set (i) in increasing order of b and gases given in set (ii) in decreasing order of a, are arranged below. Select the correct order from the following.
1) (i) He < H2< CO2< O2 (ii) CH4 > H2 > O2
2) (i) O2< He < H2< CO2 (ii) H2 > O2 > CH4
3) (i) H2< He < O2< CO2 (ii) CH4 > O2 > H2
4) (i) H2< O2< He < CO2 (ii) O2 > CH4 > H2
7. A gas such as carbon dioxide would be most likely to obey the ideal gas law at
1) low temperatures and high pressures
2) high temperatures and high pressures
3) low temperatures and low pressures
4) high temperatures and low pressures
8. Correct gas equation is
9. Which of the following mixture of gases does not obey Dalton’s law of partial pressure?
1) Cl2 and SO2 2) CO2 and He 3) O2 and CO2 4) N2 and O2
10. Average molar Kinetic energy of CO and N2 at same temperature is
1) KE1 = KE2 2) KE1 > KE2 3) KE1< KE2
4) can’t say anything. Both volumes are not given
11. The temperature of a gas is raised from 27°C to 927°C. The root mean square speed of the gas
1) remains same
3) gets halved 4) gets doubled
12. Maximum deviation from ideal gas is expected from
1) CH4(g) 2) NH3(g) 3) H2(g) 4) N2(g)
13. If Z is a compressibility factor, van der waals equation at low pressure can be written as
14. The molecular velocity of any gas is..
1) Directly proportional to square root of temperature
2) Inversely proportional to the square root of temperature
3) Inversely proportional to absolute temperature
4) Directly proportional to square of temperature
Answers: 1-4; 2-3; 3-3; 4-3; 5-1; 6-3; 7-4; 8-2; 9-1; 10-1; 11-4; 12-2; 13-2; 14-1.