• 

Question 1 Oxygen (O) is diffusing through carbon monoxide (CO) in 2 mm thick layer at total pressure of 1 atm, and temperature of 20C. The partial pressure of oxygen at the two sides of the layer is 0.13 atm and 0.065 atm respectively. The diffusivity coefficient is 1.87 x 10- 5 m/s. Calculate the rate of diffusion of oxygen in Kmol/sec through 2 m area. a. Assuming oxygen is diffusing and carbon monoxide is non- diffusing. b. Assuming equimolar counter diffusion. Useful data: R = 0.082 (L.atm/mole.K), molecular weight of CO is 28, molecular weight of oxygen is 32. Question 2 Calculate the concentration of oxygen dissolved in water at 298 K when the solution is in equilibrium with air (21% O as mole percent) at 1 atm total pressure? The Henry's law constant is 4.38 x 104 atm/mol fraction. Question 3 It is desired to reduce the concentration of acetone in a gas containing 1.0 wt% acetone in air to be 0.1 wt% in absorption tower. The inlet gas flow to the tower is 25 m/h, and the total inlet pure water flow to be used to absorb the acetone is 1600 kg H0/h. The process is to operate at 300 K and a total pressure of 101.3 kPa. The equilibrium relation for the acetone (A) in the gas-liquid is yA = 1.17XA. (VA, XA are mole fractions). Given : Molecular weight of acetone 58.0 a. Calculate the Concentration of Acetone in water exit. b. Calculate the number of transfer units (NTU) using Kremsers equation. c. Calculate the number of transfer units (NTU) in the column using McCabe- Thiele method.