Given the following table of thermodynamic data,

Complete the following sentence. The vaporization of PCl₃(l) is .

Question

Given the following table of thermodynamic data, Complete the following sentence. The vaporization of PCl₃(l) is .

Quizplus · Accepted Answer

The standard free energy change for the vaporization of PCl5(l) is positive (+84.2 kJ/mol), indicating a nonspontaneous process. However, the positive value for ΔS° (+314.4 J/mol·K) indicates an increase in entropy, which favors the spontaneous direction of the reaction. At low temperatures, the positive ΔH° (+12.9 kJ/mol) will dominate, leading to nonspontaneity. At high temperatures, the positive TΔS° term will dominate, leading to spontaneity. Therefore, the vaporization of PCl5(l) is nonspontaneous at low temperature and spontaneous at high temperature.

Given the Following Table of Thermodynamic Data