For a process to be spontaneous, the total entropy of the system and its surroundings must increase; that is
Furthermore, the entropy change in the surroundings, ΔSsurr, is related to the enthalpy change for the process by the equation ΔSsurr = −ΔH/T.
- (a) Since both ΔG and ΔStotal offer criteria for spontaneity, they must be related. Derive a relationship between them.
- (b) What is the value of ΔSsurr for the photosynthesis of glucose from CO2 at 298 K?
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General Chemistry: Atoms First
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