NH$3$ air mixture containing $5\%$ NH$3$ is scrubbed with water to remove NH$3,5000$ kg$/$hr of

gas mixture is to be processed with $2,00,000$ kg$/$hr of water to reduce NH$3$ in the exit gas to

$0\mathrm{.}15\%.$ Calculate the height of packing required assuming dilute solutions are involved.

Equilibrium relation is given by Y $=20$ X where X$,$ Y $=$ mole fraction of NH$3$ in liquid and

vapor. HTU $=2$m