Answer to Question #106175 in Physical Chemistry for Nikesh

Question

Give the statements of Zeroth, First, Second and the Third laws of thermodynamics
and outline their significance.

Answer 1

0: If two systems are both in thermal equilibrium with a third system then they are in thermal equilibrium with each other.

1: The law of conservation of energy states that the total energy of an isolated system is constant; energy can be transformed from one form to another, but can be neither created nor destroyed.

2: When two initially isolated systems in separate but nearby regions of space, each in thermodynamic equilibrium with itself but not necessarily with each other, are then allowed to interact, they will eventually reach a mutual thermodynamic equilibrium. The sum of the entropies of the initially isolated systems is less than or equal to the total entropy of the final combination. Equality occurs just when the two original systems have all their respective intensive variables (temperature, pressure) equal; then the final system also has the same values.

3: The entropy of a perfect crystal of any pure substance approaches zero as the temperature approaches absolute zero.