Table 18.

Corrected Values of the Enthalpy of Formation ${\mathrm{\Delta }}_{\mathrm{f}}{H}_{\text{298K},\text{corr}}^{°}$ (kJ/mol) Computed Using the G3MP2B3 Model Chemistry

name	formula	CAS registry no.	${\mathrm{\Delta }}_{\mathrm{f}}{H}_{\text{298K}}^{°}\left(\text{expt}\right)$	${\mathrm{\Delta }}_{\mathrm{f}}{H}_{\text{298K}}^{°}\left(\text{corr}\right)$ G3MP2B3	residual
Alkanes, Normal
ethane	C2H6	74-84-0	−84.4 ± 0.4	−84.3	0.1
propane	C3H8	74-98-6	−104.7 ± 0.6	−105.0	−0.3
butane	C4H10	106-97-8	−125.9 ± 0.4	−126.1	−0.2
pentane	C5H12	109-66-0	−146.8 ± 0.6	−147.1	−0.3
hexane	C6H14	110-54-3	−167.2 ± 0.8	−168.1	−0.9
heptane	C7H16	142-82-5	−187.8 ± 0.8	−189.2	−1.4
Alkanes, Branched
isobutane	C4H10	75-28-5	−134.4 ± 0.4	−134.4	0.0
isopentane	C5H12	78-78-4	−153.7 ± 0.6	−153.3	0.4
2-methylpentane	C6H14	107-83-5	−174.3 ± 1.0	−174.3	0.0
2-methylhexane	C7H16	591-76-4	−195.0 ± 1.3	−195.7	−0.7
neopentane	C5H12	463-82-1	−167.9 ± 0.6	−169.0	−1.1
2,2-dimethylbutane	C6H14	75-83-2	−185.6 ± 1.0	−185.2	0.4
2,2-dimethylpentane	C7H16	590-35-2	−206.2 ± 1.3	−206.4	−0.2
Alk-1-enes
ethene	C2H4	74-85-1	52.6 ± 0.2	50.1	−2.5
propene	C3H6	115-07-1	20.2 ± 0.4	18.6	−1.6
but-1-ene	C4H8	106-98-9	0.0 ± 0.5	−0.9	−0.9
pent-1-ene	C5H10	109-67-1	−21.3	−22.4	−1.1
hex-1-ene	C6H12	592-41-6	−42.1 ± 1.2	−43.7	−1.6
Alk-1-enes, Branched
3-methylbut-1-ene	C5H10	563-45-1	−27.7 ± 1.2	−29.4	−1.7
3-methylpent-1-ene	C6H12	760-20-3	−47.0 ± 1.1	−51.5	−4.5
3-methylhex-1-ene	C7H14	3404-61-3	−68.2 ± 1.5	−72.7	−4.5
4-methylpent-1-ene	C6H12	691-37-2	−49.4 ± 0.7	−49.9	−0.4
3-ethylpent-1-ene	C7H14	4038-04-4	−69.5 ± 2.0	−73.1	−3.6
3,3-dimethylpent-1-ene	C7H14	3404-73-7	−78.5 ± 1.7	−81.5	−3.0
3,3-dimethylbut-1-ene	C6H12	558-37-2	−59.7 ± 2.0	−61.7	−2.0
Alk-n-enes, (E)
(E)-but-2-ene	C4H8	624-64-6	−11.2 ± 0.5	−11.4	−0.2
(E)-pent-2-ene	C5H10	646-04-8	−33.1 ± 1.3	−31.3	1.8
(E)-hex-2-ene	C6H12	4050-45-7	−51.7 ± 2.0	−53.0	−1.3
(E)-hex-3-ene	C6H12	13269-52-8	−49.3 ± 1.1	−51.4	−2.1
(E)-4-methylpent-2-ene	C6H12	674-76-0	−60.1 ± 1.5	−60.1	0.0
Alk-n-enes, (Z)
(Z)-but-2-ene	C4H8	590-18-1	−7.3 ± 0.5	−6.5	0.8
(Z)-pent-2-ene	C5H10	627-20-3	−28.0 ± 0.8	−26.0	2.0
(Z)-hex-2-ene	C6H12	7688-21-3	−47.9 ± 2.0	−47.8	0.1
(Z)-hex-3-ene	C6H12	7642-09-3	−46.9 ± 2.0	−45.7	1.2
Isoalkenes
2-methylprop-1-ene	C4H8	115-11-7	−17.5 ± 0.5	−17.3	0.2
2-methylbut-1-ene	C5H10	563-46-2	−35.1 ± 0.8	−35.1	0.0
2-methylpent-1-ene	C6H12	763-29-1	−58.0 ± 1.1	−56.7	1.3
2-methylbut-2-ene	C5H10	513-35-9	−41.5 ± 0.9	−40.8	0.7
Alk-1-ynes
ethyne	C2H2	74-86-2	226.7 ± 0.8	227.5	0.8
propyne	C3H4	74-99-7	185.4 ± 0.9	184.9	−0.5
but-1-yne	C4H6	107-00-6	166.1 ± 2.1	166.4	0.3
pent-1-yne	C5H8	627-19-0	144.3 ± 2.1	144.7	0.4
Alk-1-ynes, Branched
isopentyne	C5H8	598-23-2	136.4 ± 2.1	139.2	2.8
tert-hexyne	C6H10	917-92-0	106.1	106.1	0.0
Alk-2-ynes
but-2-yne	C4H6	503-17-3	148.0 ± 1.5	147.9	−0.1
pent-2-yne	C5H8	627-21-4	128.9 ± 2.1	128.9	0.0
Alkadienes
penta-1,4-diene	C5H8	591-93-5	106.3 ± 1.3	102.8	−3.5
hexa-1,5-diene	C6H10	592-42-7	85.0 ± 2.0	81.8	−3.2
Alkadienes, Conjugated
(E)-buta-1,3-diene	C4H6	106-99-0	108.8 ± 0.8	108.8	0.0
(E)-penta-1,3-diene	C5H8	2004-70-8	75.8 ± 0.7	76.8	1.0
Alkatrienes
(E)-hexa-1,3,5-triene	C6H8	821-07-8	168.0 ± 3.0	163.9	−4.1
(Z)-hexa-1,3,5-triene	C6H8	2612-46-6	172.0 ± 3.0	170.1	−1.9
Alkenynes
1-buten-3-yne	C4H4	689-97-4	295.0 ± 3.0	288.0	−7.0
(E)-pent-3-en-1-yne	C5H6	2004-69-5	259.0 ± 3.0	252.7	−6.3
(Z)-pent-3-en-1-yne	C5H6	1574-40-9	258.0 ± 3.0	254.4	−3.6
2-methylbut-1-en-3-yne	C5H6	78-80-8	259.0 ± 1.3	253.1	−5.9
Alkadiynes
butadiyne	C4H2	460-12-8	464.0	454.5	−9.5
1,5-hexadiyne	C6H6	628-16-0	416.0	412.3	−3.7
Alkendiynes
(E)-hex-3-en-1,5-diyne	C6H4	16668-68-1	538.0 ± 3.0	524.8	−13.2
(Z)-hex-3-en-1,5-diyne	C6H4	16668-67-0	541.8 ± 3.0	525.6	−16.2