Two bulbs are connected by a tube, 0.002 m in

Two bulbs are connected by a tube, 0.002 m in diameter and 0.20 m in length. Initially bulb 1 contains argon, and bulb 2 contains xenon. The pressure and temperature are maintained at 1 atm and 105oC, at which the diffusivity is 0.180 cm2/s. At time t = 0, diffusion is allowed to occur between the two bulbs. At a later time, the argon mole fraction in the gas at end 1 of the tube is 0.75, and 0.20 at the other end. Determine at the later time:
(a) The rates and directions of mass transfer of argon and xenon
(b) The transport velocity of each species
(c) The molar average velocity of the mixture