Zeroth Law of thermodynamics - If A is in thermal equilibrium with B and B is thermal Equilibrium with C then, A and C are in thermal quilibrium.

First Law of thermodynamics - Law of Energy Conservation. Energy cannot be created nor destroyed only be transformed from one form to another.

Second Law of Thermodynamics - The entropy of the Universe increases.

Third law of Thermodynamics - The entropy of all perfect crystal is zero at absolute zero (0 degree Kelvin). It is impossible by any procedure to reduce any system to the absolute zero of temperature in a finite number of idealized steps.


***********recall the four fundamental Laws of Thermodynamics (U or E,H,A,G)*********

Thermochemistry - study of the heat changes accompanying chemical reactions.