A plate tower is employed for stripping a toxic gas from a liquid polluted water stream by means of countercurrent air at atmospheric pressure and 25C. The inlet air flowrate is equal to 2000 standard cubic meters ( 1 atm, 25 .C) and is free of toxic gas and the inlet liquid concentration is 0.1 mole% toxic gas. Find the number of theoretical stages in the column to reach an outlet concentration of toxic gas in water 0.001 mole fraction. MW of toxic gas 17 g/mole MW of water 18 g/mole The absorption equilibrium at 25C is given by the relation y toxic gas - 1.414 X toxic gas