A mass-transfer process is used to remove ammonia (NH₃, solute A) from a mixture of NH₃and air, using water as the absorption solvent. At the present conditions of operation, the partial pressure of ammonia in the bulk gas phase (p_A) is 0.20 atm, and the mole fraction of dissolved NH₃in the water (x_A) is 0.040. The total system pressure is 2.0 atm, and the temperature is 30°C. At 30°C, the molar solution density is 55.6 kgmole/m³. The film mass-transfer coefficients are k_G= 1.0 kgmole/m²· s · atm, and k_L= 0.045 m/s for the gas and liquid, respectively. The equilibrium distribution data at 30°C for the NH₃-water-air system are given in the table below:

a. Prepare an equilibrium distribution plot for NH₃ as partial pressure vs. mole fraction (p_A €“ x_A). 

b. What is k_x? 

c. What are the interface compositions x_A,i and p_A,i? What are x^*_A and p^*_A? 

d. What is K_G, the overall mass-transfer coefficient based on the gas phase? 

e. What is the flux N_A for this process?

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PA (atm) CAL (kgmole/m³) PA (atm) CAL (kgmole/m³) 0.105 0.463 0.236 0.145 5.32 0.342 9.71 0.067 7.61 4.09 2.79 0.015 0.697 11.6 0.025 0.053 2.26 0.039 0.032 1.43 0.020 1.71 0.925 1.15