A gas phase decomposition reaction 2AB₃ A₂ + 3B₂
Is exothermic. What can you conclude about the spontaneity of this reaction?

Question

A gas phase decomposition reaction 2AB₃ A₂ + 3B₂ Is exothermic. What can you conclude about the spontaneity of this reaction?

Quizplus · Accepted Answer

The fact that the reaction is exothermic suggests that it releases heat, and thus has a negative delta H. According to the Gibbs free energy equation, delta G = delta H - T(delta S), where delta S is the change in entropy. For spontaneous reactions, delta G must be negative. If delta H is negative and the reaction is exothermic, then delta S must be positive to make delta G negative. Therefore, we can conclude that this reaction is spontaneous.

A Gas Phase Decomposition Reaction 2AB3 A2 + 3B2

A Gas Phase Decomposition Reaction 2AB₃ A₂ + 3B₂