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The purification of hydrogen gas by diffusion through a palladium sheet is a steady-state diffusion. The number of kilograms of hydrogen that pass per hour through a 5 mm thick sheet of palladium is 3.57 x 10-3 kg/hr, and has a cross-sectional area of 0.20 m2 at 500o Assume a diffusion coefficient of 1.0 x 10-8 m2/s, that the concentration at high-pressure side of the plate is 2.6 kg/m3, calculate the concentration in kg/m3 at the low-pressure side.