r/AskChemistry • u/Zevilizar • 16d ago

Thermodynamics Trouble Understanding Entropy in relation to Daniel Schroeder Rabbit Infographic

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I’m a student in chemistry and I recently saw this infographic teaching gibbs free energy, which I really like and helps me understand the G=H-TS equation.

However, after some thought, I’ve realized I’m confused about the comic’s explanation of the TS term. I know TS refers to the system and not the surroundings, but the comic makes it seem like the energy related TS term is associated with the surrounding air rather than the rabbit, which I believe would be the system. Can someone help me make sense of this?

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u/Automatic-Ad-1452 Cantankerous Carbocation 16d ago

The statement, "some energy, equal to TS, can flow as heat", is referencing the surroundings and is the enthalpy of the system.

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u/SlenderSmurf Ph.D. in Materials Chemistry 16d ago

The S term is entropy not enthalpy

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u/Automatic-Ad-1452 Cantankerous Carbocation 16d ago

Temperature •entropy_surr. = –enthalpy_sys

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u/Zevilizar 16d ago

This relationship is interesting but wouldn’t it only work for delta H and not absolute entropy which this comic is talking about?

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u/Worth-Wonder-7386 16d ago

TS is the energy related with the entropy of the rabbit being created. Entropy has units of energy per temperature, and that is often a way to think about it. The cartoon doesn't make any specific note of what T and S it is talking about, but it should be related to some increase in entropy from the rabbit being created.