Chapter 4, Problem 4B.11P

(a)

Interpretation Introduction

Interpretation: An expression analogous to the Clausius-Clapeyron equation, starting for the Clapeyron equation for the temperature variation of the vapour pressure of a solid has to be derived.

Concept introduction: Clapeyron equation can be used to calculate the enthalpy of various phase transitions.  The phase transition between the liquid and solid state of a substance is calculated by the following formula.

    $\left(\frac{\text{d}p}{\text{d}T}\right)=\frac{{\Delta }_{\text{trans}}H}{T\Delta V_{\text{trans}}}$

(b)

Interpretation Introduction

Interpretation: The standard enthalpy of sublimation of chloromethane at $150\text{K}$ has to be estimated.

Concept introduction: Clausius-Clapeyron expression correlates the pressure and temperature for the processes that includes the phase transitions.  Clausius-Clapeyron equation is shown below.

    $\ln \left(\frac{p_2}{p_1}\right)=-\frac{{\Delta }_{\text{vap}}H}{R}\left(\frac{1}{T_2}-\frac{1}{T_1}\right)$