A closed vessel contains equal number of nitrogen and oxygen molecules at pressure of P mm. If nitrogen is removed from the system, then the pressure will be

(1) $\mathrm{P}$                              

(2) $2\mathrm{P}$

(3) $\mathrm{P}/2$                           

(4) ${\mathrm{P}}^2$

Two vessels of capacities 3 litres and 4 litres are separately filled with a gas. The pressures are respectively 202 kPa and 101 kPa. The two vessels are connected. The gas pressure will be now, at constant temperature.

(1) 151.5 kPa                             

(2) 144 kPa

(3) 303 kPa                                 

(4) 175 kPa

2 gms of hydrogen diffuses from a container in 10 minutes. How many gms of oxygen would diffuse through the same time under similar conditions?

1. 0.5 gm                         

2. 4 gm

3. 6 gm                             

4. 8 gm

Which of the following contains the greatest number of nitrogen atoms ?

1. 500 ml of 2.0 $\mathrm{M}<mspace\; width="1em"></mspace>{\mathrm{NH}}_3$

2. One mole of ${\mathrm{NH}}_4\mathrm{Cl}$

3. $6.02<mspace\; width="1em"></mspace>\times <mspace\; width="1em"></mspace>{10}^{23}$ molecules of ${\mathrm{NO}}_2$ gas

4. 22.4 litres of ${\mathrm{N}}_2$ gas at 0ºC and 1 atm.

The temperature of a sample of gas is raised from 127ºC to 527ºC. The average kinetic energy of the gas$-$

(1) Does not changes                         

(2) Is doubled

(3) Is halved                                     

(4) Cannot be calculated 

A helium atom is two times heavier than a hydrogen molecule at 298 K, the average kinetic energy of helium is

(1) Two times that of hydrogen molecules

(2) Same as that of hydrogen molecules

(3) Four times that of hydrogen molecules

(4) Half that of hydrogen molecules

The ratio of average molecular kinetic energy of ${\mathrm{UF}}_6$ to that of ${\mathrm{H}}_2$, both at 300 K is$-$

(1) 1 : 1                       

(2) 7 : 2

(3) 176 : 1                   

(4) 2 : 7

A mono atomic gas diatomic gas and triatomic gas are mixed, taking one mole of each ${\mathrm{C}}_{\mathrm{p}}/{\mathrm{C}}_{\mathrm{v}}$ for the mixture is$-$

(1) 1.40                               

(2) 1.428

(3) 1.67                               

(4) 1.33

According to kinetic theory of gases, for a diatomic molecule

(1) The pressure exerted by the gas is proportional to the mean velocity of the molecule.

(2) The pressure exerted by the gas is proportional to the root mean square velocity of the molecule.

(3) The root mean square velocity of the molecule is inversely proportional to the temperature.

(4) The mean translational kinetic energy of the molecule is proportional to the absolute temperature.

The values of vander waals constant ‘a’ for the gases ${\mathrm{O}}_2$, ${\mathrm{N}}_2$, ${\mathrm{NH}}_3$ and ${\mathrm{CH}}_4$ are 1.36, 1.39, 4.17 and 2.253 ${\mathrm{lit}}^2$ atom mol^-2 respectively. The gas which can most easily be liquefied is$-$

(A) ${\mathrm{O}}_2$                                 

(B) ${\mathrm{N}}_2$

(C) ${\mathrm{NH}}_3$                              

(D) ${\mathrm{CH}}_4$