Thermodynamics
The branch of science dealing with energy, its transformations, and the direction in which processes occur.
Unit
J
In depth
Chemical thermodynamics predicts whether a reaction is possible and how far it will go, using only bulk properties measured at the start and end. It says nothing about how fast a change occurs — that is the province of kinetics — so a reaction can be thermodynamically favourable yet immeasurably slow.
Examples in the real world
Predicting that diamond is thermodynamically unstable relative to graphite, though the conversion takes geological time.