Given that the density of air at 740 torr and 27°c is 1.146 g l1, calculate the mole fraction and partial pressure of nitrogen and oxygen assuming that: air consists of only these two gases, 6. (a) (i) ii) air also contains 1.00 mole percent ar assume that air is a perfect gas. (10) (b) the density of water vapour at 1.00 bar and 383 k is 0.5678 g l (i) determine the molar volume, vm, of water and the compression factor, z, from these data (ii) calculate z from the van der waals equation with a = 5.464 l2 atm mol-2 and b 0.0305 l mol