Heats of Formation (ΔH_f^o; kcal/mol)

(All values are for gases at 25 ^oC and 1 atm. Elements that are gaseous under these conditions

are taken as 0 kcal/mol. Updated values appear in red.)

Index :

• Alcohols
• Aldehydes/Ketones
• Alkanes
  • Acyclic Alkanes
  • Cycloalkanes
• Alkenes
• Alkynes
• Atoms and Radicals
• Alkyl Halides
• Aromatics
• Ethers
• Other Compounds and Elements
• Atoms and Radicals
  

Cycloalkanes	#C	ΔHfo
cyclopropane	3	+12.7
cyclobutane	4	+6.6
cyclopentane	5	-18.3
cyclohexane	6	-29.5
methylcyclohexane	7	-37.0
cis-1,2-dimethylcyclohexane	8	-41.1
trans-1,2-dimethylcyclohexane	8	-43.0
cis-1,3-dimethylcyclohexane	8	-44.1
trans-1,3-dimethylcyclohexane	8	-42.2
cis-1,4-dimethylcyclohexane	8	-42.2
trans-1,4-dimethylcyclohexane	8	-44.0
cycloheptane	7	-28.2
cyclooctane	8	-29.7

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Alkenes	#C	ΔHfo
ethene (ethylene)	2	+12.5
propene (propylene)	3	+4.8
propadiene (allene)	3	+45.5
1-butene	4	-0.2
(Z)-2-butene (cis)	4	-1.7
(E)-2-butene (trans)	4	-2.7
2-methylpropene	4	-4.3
1,3-butadiene	4	+26.3
1-pentene	5	-5.0
(Z)-2-pentene	5	-6.6
(E)-2-pentene	5	-7.7
(Z)-1,3-pentadiene	5	+19.5
(E)-1,3-pentadiene	5	+18.2
1,4-pentadiene	5	+25.3
2-methyl-1-butene	5	-8.4
2-methyl-2-butene	5	-10.0
1-hexene	6	-10.2
cis-2-hexene	6	-11.6
trans-2-hexene	6	-12.6
(E)-3-methyl-2-pentene	6	-15.2
(Z)-3-methyl-2-pentene	6	-14.8
2-ethyl-1-butene	6	-13.4
2,3-dimethyl-2-butene	6	-16.8
2.3-dimethyl-1-butene	6	-15.7
cyclohexene	6	-1.2
1-methyl-1-cyclohexene	7	-19.4

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Alkynes	#C	ΔHfo
ethyne (acetylene)	2	+54.5
propyne (methylacetylene)	3	+44.2
1-butyne	4	+39.5
2-butyne	4	+34.8
1-pentyne	5	+34.5
2-pentyne	5	+30.8
1-hexyne	6	+29.2
2-hexyne	6	+25.7
3-hexyne	6	+25.2

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Alkyl Halides	#C	ΔHfo
chloromethane	1	-19.6
bromomethane	1	-8.5
iodomethane	1	+3.4
chloroethane	2	-26.8
bromoethane	2	-14.8
iodoethane	2	-1.9
1-chloropropane	3	-31.5
2-chloropropane	3	-34.6
1-bromopropane	3	-20.8
2-bromopropane	3	-23.8
1-iodopropane	3	-7.2
2-iodopropane	3	-9.6
chlorocyclopentane	5
chlorocyclohexane	6	-39.1

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Alcohols	#C	ΔHfo
methanol	1	-48.1
ethanol	2	-56.2
1-propanol	3	-61.0
2-propanol	3	-65.2
1-butanol	4	-65.7
2-butanol	4	-70.0
2-methyl-1-propanol	4	-67.8
2-methyl-2-propanol	4	-74.7

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Aldehydes/Ketones	#C	ΔHfo
formaldehyde	1	-27.7
acetaldehyde	2	-4.8
propionaldehyde	3	-45.1
n-butyraldehyde	4	-50.6
isobutyraldehyde	4	-51.6
2-propanone (acetone)	3	-52.2
2-butanone (methyl ethyl ketone, MEK)	4	-57.0

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Aromatics	#C	ΔHfo
benzene	6	+19.8
chlorobenzene	6	+13.0
nitrobenzene	6	+16.4

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Ethers	#C	ΔHfo
dimethyl ether	2	-44.0
oxirane (ethylene oxide)	2	-12.6
ethyl methyl ether	3	-51.7
methyl oxirane (propylene oxide)	3	-22.6
diethyl ether	4	-60.4
methyl n-propyl ether	4	-56.9
isopropyl methyl ether	4	-60.2
ethyl vinyl ether	4	-33.5
tetrahydrofuran	4	-44.0

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Other Compounds and Elements	ΔHfo
HCl	-22.1
HBr	-8.7
HI	+6.3
H2O (g)	-57.8
H2O (l)	-68.3
Br2 (g)	+7.4
I2 (g)	+14.9
CO2	-94.05
H2	0
O2	0
Cl2	0
C (graphite)	0

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Heats of Formation of radicals can be calculated by the following equation:

ΔH_f^o (R^.) = ΔH_f^o (RH) + DH^o (RH) - ΔH_f^o (H^.)

See Heats of Reaction for help.

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