Agas stream flows at a rate of 14 m3/s at 322 k and 172 kpa. it consists of a mixure of 52 mole % ammonia in air. the gas enters through the bottom of a packed-bed gas absorber, where it flows countercurrent to a stream of pure liquid water that absorb 90% of all of the ammonia, and virtually no air. the absorber vessel is cylindrical with an internal diameter of 2.5 m. (a) neglecting the evaporation of water, calculate the ammonia mol fraction in the gas leaving the absorber. (b) calculate the outlet gas mass velocity (defined as mass flow rate per unit empt