e.u.
entropy unit
Molar entropyexact by definition
The entropy unit is the calorie per mole kelvin, 4.184 J/(mol·K) on the thermochemical calorie. It is old chemistry shorthand: standard entropies were tabulated in e.u. through the middle of the twentieth century, where liquid water is 16.7 e.u. and the same figure is 69.9 J/(mol·K) today.
Watch out: Sources built on the IT calorie give 4.1868 instead of 4.184, a 0.1% difference. Older tables rarely state which calorie they used.
| 1 e.u. | 4.184 J/(mol·K) |
Solvers that use molar entropy