A packed column is used to reduce the levels of a pollu- tant in a gas stream from a mole fraction of 0.025 to a mole fraction of 0.00015. The gas stream lows at a rate of 10.0 m3/min while pure water enters the top of the column at a rate of 15.0 kg/min. The 2.25 m diameter tower will be packed with 19 mm ceramic Raschig rings, providing an interfacial surface area-to-volume ratio of 262 m2/m3. The overall mass-transfer coefficient based on the gas-phase driving force is 69.4 mol/m2 h. The system operates at 40°C and atmospheric pressure. The pollutant follows the Henry's law relation with the Ben- ry's law constant equal to 1.75 x 105 Pa. Probiem 27 The total height of packing required to achieve the de- sired separation is most nearly (A) 1.61 ㎡ (B) 5.81 m (C) 20.3 r (D) 53.5 m