Question

Is this spontaneous or nonspontaneous at high temperatures?

H°: positive
S°: positive
Low temperature: nonspontaneous a) Spontaneous
b) Nonspontaneous
c) Cannot determine
d) Depends on the reaction

Answer 1

The reaction is spontaneous at high temperatures because the positive entropy change (S°) contributes more significantly to the Gibbs free energy equation at higher temperatures, leading to a negative ΔG.

The answer is option ⇒a) Spontaneous

Step-by-step explanation:

According to the Gibbs free energy equation ΔG = ΔH - TΔS, when both ΔH (enthalpy change) and ΔS (entropy change) are positive, the sign of ΔG (the free energy change) depends on the temperature due to the term –TΔS becoming larger at higher temperatures.

At low temperatures, the reaction is nonspontaneous because the TΔS term is not large enough to overpower the positive ΔH, but at high temperatures, the increasing value of the TΔS product can make ΔG negative, thus making the reaction spontaneous.

The answer is option ⇒a) Spontaneous