11.Same gas is confined to two containers A and B. The pressure, volume and temperature (K) of gas in A are three times as compared to that in B. If the mass of gas in A is x g, then the mass in B would be

12.Each of the four species, hydrogen sulphide (I), protium oxide (II), hydrogen chloride (III) and chlorine (IV) at S.T.P. have been put into four separate vessel each of one litre capacity. The largest number of molecules are present in

13.The vapour density of gas X is 4 times that of Y. If molecular mass of X is

14.The distance between the centres of the molecules at the closest approach is called

15.Three flasks of 2 L capacity were separately filled with argon, oxygen and ozone respectively under similar conditions. The ratio of number of atoms in the flasks is