Chapter 11, Problem 11.87SP

Interpretation Introduction

Interpretation:

Mole fraction of cyclopentane in a mixture of cyclopentane and cyclohexane has to be calculated that has vapor pressure of $212mmHg$ at $30°C.$

Concept Introduction:

Vapor pressure of a substance is known as the pressure exerted by molecules on the vapor phase when they are in equilibrium with their actual phase which can be liquid or solid.

A solution is at least made up of two components.  Mole fraction of a component in the solution correlates to the ratio of number of moles of that component to the total number of moles.  It is expressed as,

$\text{Mole fraction = }\frac{number\text{ of moles of a component}}{total\text{ number of moles in the solution}}$

Raoult’s law deals with the vapor pressure of pure solvents and solution which states –

Vapor pressure of solution is equivalent to the product of vapor pressure of the solvent in its pure state and mole fraction of solvent in the solution.  It is expressed as,

$P_A=P_A^{°}{X}_A$

Where,

$\begin{array}{l}{P}_A\text{ = vapor pressure of solution}\\ {\text{P}}_A^{°}\text{ = Vapor pressure of pure solvent}\\ {\text{X}}_A\text{= mole fraction of solvent in the solution}\end{array}$