Max. Marks: $7\mathrm{.}5$

Time: $30$ minutes

Under which reflux ratio condition in distillation column, finite size of condensor and reboiler is used. $(1)$

Why do you subtract one plate from the theoretical number of plates? $(0\mathrm{.}5)$

What will happen if the relative volatility of the liquid mixture value is equal to one?$(1)$

If the value of feed line $q=1\mathrm{.}5,$ what is the slope of the $q-$line? $(0\mathrm{.}5)$

Why the simple distillation also called as differential distillation? Briefly explain. $(1\mathrm{.}5)$

Write the assumptions used in Mc$-$Cabe Thiele Method. $(1)$

A continuous rectifying column handles a mixture consisting of $40$ percent of methanol by mass and $60$ percent of water at the rate of $4k\frac{g}{s},$ and separates it into a product containing $97$ percent of benzene and a liquid containing $98$ percent toluene. The feed is liquid at its boiling$-$point. $($a$)$ Calculate the molar flows of distillate and residue. $(2)$