A $150$kmo$\frac{l}{h}$ gas consisting of ammonia $($A$)$ and air $($C$)$ will be washed with water $($S$)$ in a plate

column operating at $20C$ and $800mmHg.$ Gas contains $20$ percent ammonia by volume and this will

be reduced to $1\mathrm{.}96$ percent. The water, which is ammonia$-$free, will be supplied at a flow rate of $2581$

$k\frac{g}{h}.$ Calculate:

a$)$ The concentration of liquid solution leaving the column,

b$)$ The percentage recovery of ammonia,

c$)$ The number of equilibrium plates needed,

d$)$ The quantity of ammonia transferred from gas to liquid on each equilibrium plate.

Equilibrium data for ammonia$-$water at these conditions are: