Ammonia (NH₃) in air is being absorbed into water within the enclosed tank shown in the figure (next page). The liquid and gas phases are both well mixed, and mass-transfer occurs only at the exposed gas€“liquid interface. The diameter of the cylindrical tank is 4.0 m, and the total liquid volume inside the tank is constant. The bulk gas partial pressure of NH₃is maintained at 0.020 atm, and the total gas pressure is constant at 1.0 atm. The system is isothermal at 20°C. The inlet volumetric flow rate of water is 200 L/h (0.20 m³/hr), and there is no NH₃in the inlet liquid stream (i.e., c_AL,₀= 0). You may assume that Henry€™s law adequately describes the equilibrium distribution of NH₃between the gas and liquid phases, given by P_A,i= H · c_AL,i, where H = 0.020 m³atm/kgmole. The mass transfer coefficients for the gas and liquid films are k_G= 1.25 kgmole/m²· hr · atm and k_L= 0.05 kgmole/(m²· hr · (kgmole/m³)), respectively.

a. Develop a material balance equation for NH₃ (solute A). Then determine c_AL, the concentration of dissolved NH₃ in the outlet liquid stream. In material balances involving inter phase mass-transfer, base the material balance on one phase. For this process, consider a material balance on NH₃ based on the liquid phase.
b. Determine p_A,i the partial pressure of NH₃ at the gas€“liquid interface, and c_AL,i, the dissolved NH₃ concentration at the liquid side of the gas€“liquid interface.
c. Determine W_A, the total rate of ammonia transfer.
d. 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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Closed Tank Air + NH, IN GAS well-mixed P = 1.0 atm Air + NH, OUT PA = 0.02 atm PA= 0.02 atm Water + Fresh water dissolved O3 IN Absorption: CAL OUT Vo = 0.20 m3/h CALO= 0 gmole/m3 Vo= 0.20 m³/h CAL = ? LIQUID