mass transfer

A solid of silica 2mm thick is porous, with a void fraction of 0.5 and a tortuosity of 4.0. The pores are filled with water at 300K. At one face the concentration of NaCl is held at 0.5gmol /liter and fresh water flows rapidly past other face. Neglecting any other resistance but that in the porous solid, determine the diffusion of NaCl. The gas hydrogen at 30 degree Celsius, and 0.03 atm partial pressure is diffusing through a membrane of vulcanized neoprene rubber 1mm thick. The pressure of hydrogen on the other side of neoprene is zero. Calculate the steady-state flux, assuming the only resistance to diffusion is in the membrane. The solubility S of hydrogen gas in neoprene at 30 degree Celsius is 0.06m3 (at STP of zero degree Celsius and 1atm ) /m3 solid atm and the diffusivity DAB is 31010m2/s at 30 degree Celsius. Estimate the flux if the temperature is increased twice