cal/(mol·K)

calorie per mole kelvin

Molar entropyexact by definition

The calorie per mole per kelvin, historically called the entropy unit, is exactly 4.184 J/(mol·K) using the thermochemical calorie. The factor is exact by definition of that calorie. Older American thermochemical tables list standard entropies in these units, where the gas constant R is 1.987 cal/(mol·K), often rounded to 2.

Watch out: The abbreviation e.u. for entropy unit appears in mid-twentieth-century literature and means exactly this unit. It is not the same as anything in modern SI naming, and it should be converted rather than carried forward.

1 cal/(mol·K) 4.184 J/(mol·K)
Solvers that use molar entropy