Group Contributions to ΔHf

°(g) and S°(g) at 298 K*

 ΔHf° (kJ/mol)S° (J/mol K)
Alkane, gauche correction3.3 
Alkene, gauche correction2.1 
cis correction4.2 
ortho correction2.4-6.7
Cyclopropane115.4134.2
Cyclopropene224.5140.4
Cyclobutane110.5124.6
Cyclobutene124.6121.2
Cyclopentane26.3114.1
Cyclopentene24.6107.8
Cyclohexane0.078.6
Cyclohexene5.990.0
Cycloheptane26.866.5
Cycloheptene22.6 
Cyclooctane41.469.0

Reference: S.W. Benson, F.R. Cruickshank, D.M. Golden, G.R. Haugen, H.E. O'Neal, A.S. Rodgers, R. Shaw, and R. Walsh, Chem. Rev., 69, 279 (1969).