Question

In order to separate the components of a binary mixture, the relative volatility should be a) less than unity b) equal to unity c) greater than unity d) greater than zero e) To maximize liquid extraction,

Answer 1

Answer: Option (c) is the correct answer.

Explanation:

A binary mixture is defined as the mixture which contains two components in the aqueous medium. The two components are solute and solvent.

And, volatility is defined as the ability of a liquid solution or substance to readily change into vapors.

For a binary solution the expression for relative volatility is as follows.

              $\alpha = \frac{\frac{y_{i}}{x_{i}}}{\frac{y_{j}}{x_{j}}}$ = $K_{i}/K_{j}$

where,    $\alpha$ = relative volatility of more volatile component i

               $y_{i}$ = vapor-liquid equilibrium concentration of component i in the vapor phase

               $x_{i}$ = vapor-liquid equilibrium concentration of component i in the liquid phase

                $y_{j}$ = vapor-liquid equilibrium concentration of component j in the vapor phase

                 $x_{j}$ = vapor-liquid equilibrium concentration of component j in the liquid phase

So, when $\alpha$ > 1 then separation by distillation is easier in nature.

Thus, we can conclude that in order to separate the components of a binary mixture, the relative volatility should be greater than unity.