The degradation of phosgene (COCl₂) into CO and Cl₂ happens to be non-spontaneous at room temperature and standard state conditions (273 K, 1 atm). What change in temperature must occur to make this a spontaneous reaction?

Question

Quizplus · Accepted Answer

For a reaction to become spontaneous, the Gibbs free energy change ($\Delta G$) must be negative. Given that the degradation of phosgene is non-spontaneous at room temperature, and assuming the reaction is endothermic ($\Delta H > 0$) and leads to an increase in disorder ($\Delta S > 0$), increasing the temperature would increase the $T\Delta S$ term in the Gibbs free energy equation ($\Delta G = \Delta H - T\Delta S$), potentially making $\Delta G$ negative and the reaction spontaneous.

The Degradation of Phosgene (COCl2) into CO and Cl2 Happens

The Degradation of Phosgene (COCl₂) into CO and Cl₂ Happens