Chapter 13, Problem 102E

Interpretation Introduction

Interpretation:

The mass of ethylene glycol is to be calculated.

Concept Introduction:

The moles $\left(n\right)$ are defined as the ratio of mass to the molar mass.

$n=\frac{\text{Mass}}{\text{Molar mass}}$

The temperature at which change of liquid state to a solid-state take is termed as freezing point.

The freezing point depression is as follows:

$\Delta T_{\text{f}}=m\times K_{\text{f}}$

Here, $\Delta T_{\text{f}}$ is the change in temperature of the freezing point in $\text{C}_{\circ }$, $m$ is the molality

of the solution in $\frac{\text{mol solute}}{\text{kg solvent}}$ and $K_{\text{f}}$ is the freezing point depression constant for the solvent.

Molality of a solution is defined as a number of moles of solute to the kilogram solvent.

$\text{molality}=\frac{\text{moles solute}}{\text{kilogram solvent}}$

For water:

$K_{\text{f}}=1.86\frac{\text{C}\text{ kg solvent}}{\text{mol solute}}$