Chapter 5, Problem 5.10E

(a)

Interpretation Introduction

Interpretation:

Approximate molar mass of the compound has to be calculated.

Concept introduction:

Freezing point depression:

The lowering of the vapor pressure of a solvent by a solute leads to a lowering of the freezing point of the solution relative to that of the pure solvent.  This effect is called as the freezing point depression.  The mathematical relationship is given below.

  $\Delta T_f=T_f{}^{\circ }-T_f=K_f{m}_c$

Where, $\Delta T_f$ is freezing point depression, $T_f$ is the freezing point of solution, $T_f{}^{\circ }$ is the freezing point of pure solvent, $K_f$ is the freezing point depression constant and $m_c$ is the colligative molality.

(b)

Interpretation Introduction

Interpretation:

When the empirical formula of the compound is $C_3{H}_{2}Cl$. The molecular formula of the compound has to be calculated

(c)

Interpretation Introduction

Interpretation:

More accurate molar mass of the compound has to be calculated