Hydrogen gas at 25 degree Celcius and 2.5 atmosphere flows through a rubber tubing of 12 mm inside radius and 24 mm outside radius. The binary diffusion coefficient of hydrogen is 2.1 x 10-8 m2/s and...

Hydrogen gas at 25  degree Celcius  and 2.5 atmosphere flows through a
rubber tubing of 12 mm inside radius and 24 mm outside radius.
The binary diffusion coefficient of hydrogen is 2.1 x 10-8 m2/s
and the solubility of hydrogen is 0.055 m3 of hydrogen per m3 of
rubber at 1 atmosphere. If the molecular mass for hydrogen gas
is taken as 1.9986 gm/mol, and the concentration of hydrogen
at the outer surface of tubing is negligible, calculate the
diffusion flux rate of hydrogen per meter length of rubber
tubing.