(40 Points) 10 M sodium hydroxide is used to remove H2S from biogas gas containing 5% H2S in a small cylindrical wetted wall column (ID x H of 0.10 x1.0 m) operates at 22 C. At the column conditions, the solubility of H2S in sodium hydroxide solution is 100 mol/m3 and the diffusion coefficient of H2S is 1x10-9 m/s. The sodium hydroxide solution enters the column at NReav 20. Assuming the density and viscosity of the sodium hydroxide solution is the same as water, i.e., 1000 kg/m3 and 1.0 CP. a) Calculate the thickness of the liquid layer and the average liquid velocity. b) Calculate the average mass transfer coefficient. c) Calculate the average concentration of H2S in the liquid at the column outlet. d) Calculate the rate of absorption of H2S in the column