Question

Explain how the third law of thermodynamic can be used for the evolution of absolute entropy of a substance

Answer 1

• The third law of thermodynamics states that the entropy of any perfectly ordered, crystalline substance at absolute zero is zero. 
• At temperatures greater than absolute zero, entropy has a positive value, which allows us to measure the absolute entropy of a substance.

• The third law of thermodynamics states that the entropy of a system at absolute zero is a well-defined constant. 

• This is because a system at zero temperature exists in its ground state, so that its entropy is determined only by the degeneracy of the ground state