A gas bulb of 1 litre capacity contains 2.0 $$\times$$ 10²¹ molecules of nitrogen exerting a pressure of 7.57 $$\times$$ 10³ Nm^-2. Calculate the root mean square (r.m.s) speed and the temparature of the gas molecules. If the ratio of the most probable speed to the root mean square speed is 0.82, calculate the most probable speed for these molecules at this temparature.

At room temperature the following reacton is procedd nearly to completion:

2NO + O₂ $$\to$$ 2NO₂ $$\to$$ N₂O₄

The dimer, N₂O₄, solidifies at 262 K. A 250 ml flask and a 100 ml flask are separated by a stop-cock. At 300 K, the nitric oxide in the larger flask exerts a pressure of 1.053 atm. and the smaller one contains oxygen at 0.789 atm. The gases are mixed by the opening stopcock and after the end of raction the flasks are cooled at 220K. Neglecting the vapour pressure of the dimer, find out the pressure and composition of the gas remaining at 220 K. (Assume the gases to behave ideally)

Calculate the volume occupied by 5.0 g of acetylene gas at 50^oC and 740 mm pressure.

Calculate the root mean square velocity of ozone kept in a closes vessel at 20^oC and 82 cm mercury pressure.