Please solve them all and show work. Thank you!

Steady-State Diffusion 1. Question 6.6 The purification of hydrogen gas by diffusion through a palladium sheet was discussed in Section 6.3. Compute the number of kilograms of hydrogen that pass per hour through a 5-mmthick sheet of palladium having an area of 0.20m2 at 500C. Assume a diffusion coefficient of 1.0108m2/s, that the respective concentrations at the high- and low-pressure sides of the plate are 2.4 and 0.6kg of hydrogen per cubic meter of palladium, and that steady-state conditions have been attained. 2. Question 6.8 A sheet of BCC iron 1mm thick was exposed to a carburizing gas atmosphere on one side and a decarburizing atmosphere on the other side at 725C. After having reached steady state, the iron was quickly cooled to room temperature. The carbon concentrations at the two surfaces of the sheet were determined to be 0.012 and 0.0075wt%, respectively. Compute the diffusion coefficient if the diffusion flux is 1.4108kg/m2s. Hint: convert the concentrations from weight percent to kilograms of carbon per cubic meter of iron. Nonsteady-State Diffusion 3. Question 6.11 Determine the carburizing time necessary to achieve a carbon concentration of 0.45wt% at a position 2mm into an iron-carbon alloy that initially contains 0.20wt%C. The surface concentration is to be maintained at 1.30wt%C, and the treatment is to be conducted at 1000C. Use the diffusion data for -Fe in Tables. Factors That Influence Diffusion 4. Question 6.23 The accompanying figure shows a plot of the logarithm (to the base 10) of the diffusion coefficient versus reciprocal of the absolute temperature for the diffusion of iron in chromium. Determine values for the activation energy and preexponential