At constant temperature, 200 cm³ of N₂ at 720 mm and 400 cm³ of O₂ at 750 mm pressure are put together in a one-litre flask. The final pressure of the mixture is- 

1. 111 mm

2. 222 mm

3. 333 mm

4. 444 mm

The rate of diffusion of two gases A and B is in the ratio of 1:4 and the B and C in the ratio 1:3 the rate of diffusion of C with respect to A is 

1. 1/12

2. 12

3. 3

4. 4

A sample of air contains only N₂, O₂ and H₂O. It is saturated with water vapours and the total pressure of 640 torr. The vapoure pressure of water is 40 torr and the molar ratio of N₂:O₂ is 3:1. The partial pressure of N₂ in the sample in 

1. 480 torr

2. 600 torr

3. 525 torr

4. 450 torr

The temperature at which the r.m.s velocity of carbon dioxide becomes the same as that of nitrogen at 21⁰C is-

1. 462 ^oC

2. 273 K

3. 189 ^oC

4. 546 K

At what temperature will the total K.E. of 0.3 mol of He be the same as the total K.E. of 0.4 mol of Ar at 400 K

1. 400K

2. 300K

3. 346K

4. 533K

The density of O₂(g) is maximum at-

1. STP

2. 273 K and 2 atm 

3. 546 K and 1 atm

4. 546 K and 2 atm

20 L of SO₂ diffuses through a porous partition in 60s. Volume of O₂ diffuse under similar condition in 30s will be:-

1. 12.14 L

2. 14.14 L

3. 18.14 L

4. 28.14 L

In van der Waal's equation of state for a non-ideal gas, the term that accounts for the intermolecular force is-

1. V-b

2. (P+a/V²)

3. RT

4. (RT)^-1

At moderate pressure, the van der Waal's equation becomes:

1. PV_m = RT

2. P(V_m-b) = RT

3. (P+a/V²_m) (V_m )= RT

4. P = RT/V_m + a/V²_m

The compressibility factor for a real gas at high pressure is:-

1. 1

2. 1+Pb/RT

3. 1-Pb/RT

4. 1-RT/Pb