Chapter 10, Problem 122CP

Interpretation Introduction

Interpretation:

The fraction of moles of $\text{NaCl}$ existing as ion pairs and the freezing point of the solution has to be calculated.

Concept Introduction:

Mole fraction of a compound can be defined as the number of moles of a substance to the total number of moles present in them. The mole fraction can be calculated by,

$\text{Mole}\text{fraction}\text{of}\text{compound=}\frac{\text{Number}\text{of}\text{moles(in}\text{mol)}}{\text{Total}\text{number}\text{of}\text{moles(in}\text{mol)}}$

Freezing point of solution can be calculated from the equation,

${\text{ΔT}}_{\text{f}}{\text{=K}}_{\text{f}}\text{m}$

${\text{ΔT}}_{\text{f}}$ = change in freezing point

${\text{K}}_{\text{f}}$ = molal depression freezing point constant

m   = moles of solute particles