Wastewater containing solute A at concentration of 1.0 · 10 gmole/m³enters an open tank at a volumetric flow rate of 0.20 m³/min, and exits at the same rate, as shown in the figure below. Solute A is released wastewater surface to the surrounding air by a gas€”liquid interface mass-transfer process. The surrounding air effectively serves as an infinite sink so that the bulk gas p_A‰ˆ 0. The total system pressure is 1.0 atm. The diameter of the cylindrical tank is 4.0 m, and the depth of the liquid in the tank is 1.0 m. At the conditions of operation, the mass-transfer coefficients for liquid and gas films are k_L= 5 · 10^-4kgmole/(m²· s · (kgmole/m³)), and k_G= 0.01 kgmole/ m²· s · atm. The concentrations are in the Henry€™s law region, where p_A,i= H · c_AL,iwith H = 10.0 m³atm/kgmole.

a. Determine the % resistance to mass-transfer in the liquid film.
b. Determine the bulk concentration c_AL in the exiting liquid stream, and c_AL,i the concentration of solute A at the liquid interface.
c. In the above system, the flux N_A would increase by increasing which of the following: the liquid volume level in the tank at fixed surface area; the agitation intensity of the bulk liquid; the agitation intensity of the bulk gas; the inlet liquid volumetric flow rate; the system temperature.

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Open Tank PA=0 atm, P = 1.0 atm Wastewater Treated wastewater CAL well-mixed Vo = 0.2 m/min CALO = 0.001 gmole/m3 CAL = ?