Callen H.B - Thermodynamics And An Introduction To Thermostatistics · Problem 13.2-6

IRREVERSIBLE THERMODYNAMICS

Physics — Statistical Mechanics · chemical-reactions-ideal-gases

Problem

At temperatures above

\sim 500

K phosphorus pentachloride dissociates according to the reaction

\text{PCl}_5 \rightleftharpoons \text{PCl}_3 + \text{Cl}_2

\text{PCl}_5

sample of

1.9 \times 10^{-3}

Kg is at a temperature of 593 K and a pressure of

0.314 \times 10^5

Pa. After the reaction has come to equilibrium the system is found to have a volume of 2.4 liters (or

2.4 \times 10^{-3}

^3

). Determine the equilibrium constant. What is the ``degree of dissociation'' (i.e., the degree of reaction

\varepsilon

for this dissociation reaction; recall equation 6.53)?