How does temperature affect the standard emf according to the provided relationships?

Prepare for the ACS Physical Chemistry: Thermochemistry Test with detailed questions, flashcards, hints, and explanations. Get ready to excel in the exam!

The standard electromotive force (emf) of a reaction is influenced by temperature, particularly through its relationship with Gibbs free energy and the entropy change of the reaction. The standard emf can be calculated using the equation:

[ E^\circ = -\frac{\Delta G^\circ}{nF} ]

where ( E^\circ ) is the standard emf, ( \Delta G^\circ ) is the change in Gibbs free energy, n is the number of moles of electrons transferred, and F is Faraday's constant.

Gibbs free energy change (( \Delta G^\circ )) is temperature-dependent and can be expressed using the equation:

[ \Delta G^\circ = \Delta H^\circ - T \Delta S^\circ ]

where ( \Delta H^\circ ) is the change in enthalpy and ( \Delta S^\circ ) is the change in entropy. As temperature (T) increases, the term (-T \Delta S^\circ) becomes more significant, particularly for reactions with a large entropy change. This interaction suggests that the standard emf will depend on both the enthalpy and entropy changes of the reaction, which inherently ties it to the concepts of therm

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