Table 1. Different Expressions for Gibbs Free Energy of Formation of Octadecane.
ΔGf (kcal/mol) |
Deviation
from database |
|||
---|---|---|---|---|
Equation | 298 K | 1000 K | 298 K | 1000 K |
ΔGf,1 = ΔHf,grnd – TSRRHO,grnd | –149.5 | –331.5 | 10.9 (6.8%) | 46.1 (12.2%) |
ΔGf,2 = ΔH̅f – TS̅RRHO | –150.7 | –344.2 | 9.6 (6.0%) | 33.4 (8.9%) |
ΔGf,3 = ΔHf,grnd – T(SRRHO,grnd + Sconf) | –158.3 | –361.3 | 2.0 (1.3%) | 16.3 (4.3%) |
ΔGf,4 = ΔH̅f – T(S̅RRHO + Sconf) | –159.6 | –373.8 | 0.8 (0.5%) | 3.8 (1.0%) |
Burcat’s database | –160.4 | –377.6 | – | – |