Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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Relative enthalpies of isomers - Comparison of 298.15K enthalpies (kJ mol^-1)

Isomers of C₄H₁₀

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	CH3CH(CH3)CH3	75285	Isobutane	0.0
b	CH3CH2CH2CH3	106978	Butane	9.2