Ninety-five percent of the acetone vapor in an 85 vol.% air stream is to be absorbed by countercurrent contact with pure water in a valve-tray column with an expected overall tray efficiency of 50 %. the column will operate essentially at 20 ºc and 101 kpa pressure. equilibrium data for acetone-water at these conditions are: mole percent acetone in water 3.30 7.20 11.7 17.1 acetone partial pressure in air, torr 30.00 62.80 85.4 103.0 calculate:

(a) the minimum value of s/g, the ratio of moles of water per mole of air.

(b) the number of equilibrium stages required using a value of s/g of 1.25 times the minimum. ( indicate operating line obviously)