All Flashcards
What is the effect of a negative ΔG°?
The reaction is spontaneous (exergonic).
What is the effect of a positive ΔG°?
The reaction is nonspontaneous (endergonic).
What is the effect of ΔH° < 0 and ΔS° > 0 on spontaneity?
The reaction is always spontaneous.
What is the effect of ΔH° > 0 and ΔS° < 0 on spontaneity?
The reaction is never spontaneous.
What is the effect of high temperature on a reaction with ΔH° > 0 and ΔS° > 0?
The reaction becomes spontaneous.
What is the effect of low temperature on a reaction with ΔH° < 0 and ΔS° < 0?
The reaction becomes spontaneous.
Differentiate between exothermic and endothermic reactions.
Exothermic: Releases heat (ΔH° < 0). Endothermic: Absorbs heat (ΔH° > 0).
Differentiate between positive and negative entropy change.
Positive ΔS°: Disorder increases. Negative ΔS°: Disorder decreases.
Differentiate between spontaneous and nonspontaneous reactions.
Spontaneous: Occurs without external help (ΔG° < 0). Nonspontaneous: Requires external help (ΔG° > 0).
Differentiate between enthalpy-driven and entropy-driven reactions.
Enthalpy-driven: Spontaneity due to heat release (ΔH°). Entropy-driven: Spontaneity due to increased disorder (ΔS°).
How do you calculate ΔG° using ΔH° and ΔS°?
Use the equation: ΔG° = ΔH° - TΔS°, where T is the temperature in Kelvin.
How do you calculate ΔG° using standard free energies of formation?
Use the equation: ΔG°rxn = ΣnΔG°f(products) - ΣnΔG°f(reactants)