All Flashcards
Define 'thermodynamic favorability'.
The tendency of a reaction to occur spontaneously.
Define a 'spontaneous reaction'.
A reaction that occurs on its own without external energy input.
Define 'enthalpy change (ΔH°)'.
The heat change in a reaction at constant pressure.
Define 'entropy change (ΔS°)'.
The change in the disorder or randomness of a system.
Define 'Gibbs Free Energy (ΔG°)'.
A measure of the spontaneity of a reaction, combining enthalpy and entropy.
Define an 'exothermic reaction'.
A reaction that releases heat to the surroundings (ΔH° < 0).
Define an 'endothermic reaction'.
A reaction that absorbs heat from the surroundings (ΔH° > 0).
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)