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.

Catalyst particles are entrapped in the center of a porous membrane material. The purpose of this is to protect the catalyst so that it can be recovered and reused. This structure shown below is immersed in an aqueous solution containing a proprietary reactant called component A. Component A can only diffuse through the top and bottom faces of this structure. The dimensions of the top face and the bottom face are same (10cm x 10cm). The thickness of the top membrane is 0.1cm and the thickness of the bottom membrane is also 0.1cm. Furthermore component A is instantaneously consumed by the catalyst at a constant rate of 144 mg/hour when it enters the compartment where the catalyst is located.   If the effective diffusivity of component A in this application is 2 x 10-5 cm2/s in the membrane calculate the concentration of component A in the surrounding solution that is needed to maintain the consumption rate. (You may assume the surrounding solution is well mixed and thus void of any…

in a 2-hour carburizing treatment, what temperature is required to obtain a 0.5% concentration of carbon at a depth of 0.5 mm below the surface of steel with a carbon concentration of 0.2%?considers that the inert gas used is enriched with carbon atoms at a concentration of 1.10% and that iron has an fcc structure

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