Consider a 4 plate binary continuous distillation column provided with a total condenser and obtain its transient response to (i) a step change in feed composition and (ii) step change in reflux ratio Data: plate efficiency =1, feed is saturated liquid; liquid holdup on each tray , reboiler holdup and condenser hold-up, all constant at 100 moles. Feed plate is 2 nd from bottom; vapor hold-up and tray dynamics are negligible. Relative volatility =2 At steady state: F=100 moles /h,B=67 moles /h,D=33 moles /h,xf=0.488,R=3 Step change in feed composition, xf from 0.488 to 0.588 Step change in reflux ratio, R, from 3 to 3.5