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 C₄H₈O

index	Species	CAS number	Name	Relative experimental enthalpy (kJ mol-1)	sketch
a	CH3COCH2CH3	78933	2-Butanone	0.0
b	CHOCH(CH3)CH3	78842	Propanal, 2-methyl-	22.8
c	CHOCH2CH2CH3	123728	Butanal	32.5
d	C4H8O	109999	Furan, tetrahydro-	54.4
e	CH2C(CH3)OCH3	116110	1-Propene, 2-methoxy-	90.0
f	C4H8O	2919235	Cyclobutanol	93.8
g	C2H3OC2H5	109922	Ethene, ethoxy-	98.4