Enthalpy: Enthalpy is the heat change. When a gas condenses into a liquid, the particles slow and enthalpy is negative.
Entropy: Entropy is a measure of disorder. When a gas condenses into a liquid, the particles align more with each other, and disorder decreases making entropy negative.
Free energy: G=H-TS
If enthalpy is negative and entropy is negative, then the equation looks like this.
G= (-) - T(-)
G= (-)+T
This means that free energy is negative at a low temperature.
