2.5-1. Amount of Absorption in a Tray Tower. An existing tower contains the equivalent of 3.0 theoretical trays and is being used to absorb SO2 from air by pure water at 293K and 1.013105Pa. The entering gas contains 20mol%SO2 and the inlet air flow rate is 150kg inert air/h m2. The entering water rate is 6000kg/hm 2. Calculate the outlet composition of the gas. (Hint: This is a trialand-error solution. Assume an outlet gas composition of, say, y1= 0.01. Plot the operating line and determine the number of theoretical trays needed. If this number is not 3.0 trays, assume another value of y1, and so on.) Ans. y1=0.009