Question

Is this spontaneous or nonspontaneous at high temperatures?

H°: negative
S°: negative
Low temperature: spontaneous a) Spontaneous
b) Nonspontaneous
c) Depends on the specific reactants
d) Cannot be determined without additional information

Answer 1

The reaction in question, having negative ΔH and negative ΔS, would be nonspontaneous at high temperatures due to the increasingly negative value of -TΔS at higher temperatures.

Step-by-step explanation:

According to the Gibbs free energy equation, ΔG = ΔH - TΔS, where ΔG represents the change in free energy, ΔH is the change in enthalpy, and ΔS is the change in entropy. When ΔH is negative and ΔS is also negative, the process is spontaneous at low temperatures but becomes nonspontaneous at high temperatures. This is due to the fact that increasing temperature (T) makes the -TΔS term more negative, which can potentially outweigh the negative ΔH and lead to a positive ΔG, indicating nonspontaneity.

In this scenario, at high temperatures, the reaction would be nonspontaneous since the negative entropy (ΔS) term becomes more significant as temperature increases, hence yielding a positive ΔG. Therefore, without needing specific details on the reactants or the exact temperature, we can determine the reaction is nonspontaneous at high temperatures.