Enthalpy of Reaction at lower temperatures [ENDORSED]

[Carlos Gonzales 1H]

Could someone please explain a little more why enthalpy of reaction has a bigger role at lower T? Thanks.

[Rachel Formaker 1E]

At lower temperatures, enthalpy of a reaction (ΔH or q_P) has a bigger influence on the entropy of a reaction because of this equation:


When T is lower, ΔS is larger, meaning that q had a larger effect on entropy.

For example, if q=10 and T=1, ΔS =10, but if q=10 and T=10, then ΔS=1

So a lower temperature (T) means that the heat transferred (q) has a greater impact on entropy (ΔS).

[Juanyi Tan 2K]

I find an explanation in the textbook to be helpful: just imagine how sneezing in a quiet environment will attract attention more than in a noisy environment. The energy transfer to a cool system where there is little thermal motion will result in a more noticeable change, leading to a greater entropy.