Which of the following permits the calculation of absolute values of entropy of a pure substance from thermal data alone?

Options

A. Second law of thermodynamics
B. Third law of thermodynamics
C. First law of thermodynamics
D. Zeroth of thermodynamics

Answer

B

Explanation

For a pure substance, this can be done by summing `q_(rev)` increments from `0 K` to `298 K`. Along with this information, we use the fact that the entropy of any pure, perfect crystalline substance approaches zero as the temperature approaches absolute zero.