196:
Moreover, values measured in the past, especially before the 1970s, can be especially unreliable and have been subject to revisions on the order of 10 kcal/mol (e.g., benzene C–H bonds, from 103 kcal/mol in 1965 to the modern accepted value of 112.9(5) kcal/mol). Even in modern times (between 1990 and 2004), the O−H bond of phenol has been reported to be anywhere from 85.8 to 91.0 kcal/mol. On the other hand, the bond dissociation energy of H
243:). The former parameter tends to be favored in theoretical and computational work, while the latter is more convenient for thermochemical studies. For typical chemical systems, the numerical difference between the quantities is small, and the distinction can often be ignored. For a hydrocarbon RH, where R is significantly larger than H, for instance, the relationship
332:) has a bond dissociation energy of 174 kcal/mol. This vast difference is accounted for by the thermodynamic stability of carbon monoxide (CO), formed upon the C=C bond cleavage of ketene. The difference in availability of spin states upon fragmentation further complicates the use of BDE as a measure of bond strength for head-to-head comparisons, and
363:). In contrast to the BDE, which is usually defined and measured in the gas phase, the BDFE is often determined in the solution phase with respect to a solvent like DMSO, since the free-energy changes for the aforementioned thermochemical steps can be determined from parameters like acid dissociation constants (p
1516:. For instance, the BDE of diiodine is calculated as twice the heat of formation of iodine radical (25.5 kcal/mol) minus the heat of formation of diiodine gas (14.9 kcal/mol). This gives the accepted BDE of diiodine of 36.1 kcal/mol. (By definition, diiodine in the solid state has a heat of formation of 0.)
486:
in organic synthesis, and volcanic emissions. The strength of the bond is attributed to the substantial electronegativity difference between silicon and fluorine, which leads to a substantial contribution from both ionic and covalent bonding to the overall strength of the bond. The C−C single bond
195:
and electrochemical methods have been used to measure bond dissociation energy values. Nevertheless, bond dissociation energy measurements are challenging and are subject to considerable error. The majority of currently known values are accurate to within ±1 or 2 kcal/mol (4–10 kJ/mol).
319:
The bond dissociation energy is an enthalpy change of a particular chemical process, namely homolytic bond cleavage, and "bond strength" as measured by the BDE should not be regarded as an intrinsic property of a particular bond type but rather as an energy change that depends on the chemical
498:
On the other end of the scale, there is no clear boundary between a very weak covalent bond and an intermolecular interaction. Lewis acid–base complexes between transition metal fragments and noble gases are among the weakest of bonds with substantial covalent character, with
491:(HC≡C−C≡CH) linking two sp-hybridized carbon atoms is also among the strongest, at 160 kcal/mol. The strongest bond for a neutral compound, including multiple bonds, is found in carbon monoxide at 257 kcal/mol. The protonated forms of CO, HCN and N
355:°) accompanying homolytic dissociation of AB into A and B. However, it is often thought of and computed stepwise as the sum of the free-energy changes of heterolytic bond dissociation (A–B → A + :B), followed by one-electron reduction of A (A +
388:. While the bond-dissociation energy is the energy of a single chemical bond, the bond energy is the average of all the bond-dissociation energies of the bonds of the same type for a given molecule. For a homoleptic compound EX
462:(C−H). The bond energy is, thus, 99 kcal/mol, or 414 kJ/mol (the average of the bond-dissociation energies). None of the individual bond-dissociation energies equals the bond energy of 99 kcal/mol.
258:(R−H) − 1.5 kcal/mol is a good approximation. Some textbooks ignore the temperature dependence, while others have defined the bond-dissociation energy to be the reaction enthalpy of homolysis at 298 K.
606:
In the gas phase, the enthalpy of heterolysis is larger than that of homolysis, due to the need to separate unlike charges. However, this value is lowered substantially in the presence of a solvent.
2176:
Cerpa, Erick; Krapp, Andreas; Flores-Moreno, Roberto; Donald, Kelling J.; Merino, Gabriel (2009-02-09). "Influence of
Endohedral Confinement on the Electronic Interaction between He atoms: A He
1924:
Bordwell, F. G.; Cheng, Jin Pei; Harrelson, John A. (February 1988). "Homolytic bond dissociation energies in solution from equilibrium acidity and electrochemical data".
1483:
956:, concerning relative strengths of bonds within a given group of compounds, and representative bond dissociation energies for common organic compounds are shown below.
408:
X. Average bond energies given in tables are the average values of the bond energies of a collection of species containing "typical" examples of the bond in question.
2258:
Connelly, Samantha J.; Wiedner, Eric S.; Appel, Aaron M. (2015-03-17). "Predicting the reactivity of hydride donors in water: thermodynamic constants for hydrogen".
351:(BDFE), has become more prevalent in the chemical literature. The BDFE of a bond A–B can be defined in the same way as the BDE as the standard free energy change (Δ
1733:
235:) refers to the enthalpy change at 0 K, while the term bond-dissociation enthalpy is used for the enthalpy change at 298 K (unambiguously denoted
69:. The enthalpy change is temperature-dependent, and the bond-dissociation energy is often defined to be the enthalpy change of the homolysis at 0
482:
Si−F is even larger, at 166 kcal/mol. One consequence to these data are that many reactions generate silicon fluorides, such as glass etching,
495:
are said to have even stronger bonds, although another study argues that the use of BDE as a measure of bond strength in these cases is misleading.
438:
In the same way, for removing successive hydrogen atoms from methane the bond-dissociation energies are 105 kcal/mol (439 kJ/mol) for
2160:
2055:
2031:
2004:
1960:
1789:
1764:
1699:
1565:
2231:
Bartmess, John E.; Scott, Judith A.; McIver, Robert T. (September 1979). "Scale of acidities in the gas phase from methanol to phenol".
2307:
2068:
1590:
1409:
About 2 times stronger than a C−C single bond; however, the π bond (~65 kcal/mol) is weaker than the σ bond
228:), which is sometimes used interchangeably. However, some authors make the distinction that the bond-dissociation energy (
175:
A variety of experimental techniques, including spectrometric determination of energy levels, generation of radicals by
1512:
The value reported as the bond-dissociation energy (BDE) is generally the enthalpy of the homolytic dissociation of a
284:
for the vibrational ground state, which reduces the amount of energy needed to reach the dissociation limit. Thus,
1816:
Kalescky, Robert; Kraka, Elfi; Cremer, Dieter (2013-08-30). "Identification of the
Strongest Bonds in Chemistry".
339:
Historically, the vast majority of tabulated bond energy values are bond enthalpies. More recently, however, the
85:
1759:. New Delhi: Medtech (Scientific International, reprint of 4th revised edition, 1998, Macmillan). p. 101.
1525:
The IUPAC Gold Book does not stipulate a temperature for its definition of bond-dissociation energy (ref. 1).
2312:
688:
528:
503:
W:Ar having a W–Ar bond dissociation energy of less than 3.0 kcal/mol. Held together entirely by the
1654:
524:
62:
1877:"Proton-Coupled Electron Transfer in Organic Synthesis: Fundamentals, Applications, and Opportunities"
2109:
1825:
1602:
188:
1996:
1659:
1984:
504:
435:
bonds in water is said to be 110.3 kcal/mol (461.5 kJ/mol), the average of these values.
261:
The bond dissociation energy is related to but slightly different from the depth of the associated
78:
66:
1857:
379:
1724:
2283:
2275:
2213:
2205:
2156:
2125:
2064:
2000:
1966:
1956:
1906:
1849:
1841:
1795:
1785:
1760:
1737:
1705:
1695:
1672:
1618:
1571:
1561:
1459:
1454:
1449:
953:
720:
277:
184:
2267:
2240:
2197:
2148:
2117:
1989:
1933:
1896:
1888:
1833:
1664:
1610:
1589:
Mulder P, Korth HG, Pratt DA, DiLabio GA, Valgimigli L, Pedulli GF, Ingold KU (March 2005).
1497:
758:
424:
172:, the conversion factor 23.060 kcal/mol (96.485 kJ/mol) for each eV can be used.
838:
1645:
Blanksby SJ, Ellison GB (April 2003). "Bond dissociation energies of organic molecules".
2113:
1829:
1606:
1901:
1876:
1464:
860:
423:
O) requires 118.8 kcal/mol (497.1 kJ/mol). The dissociation of the remaining
333:
262:
157:
2152:
324:
C=CO), which has a C=C bond dissociation energy of 79 kcal/mol, while ethylene (H
2301:
74:
47:
43:
1861:
1493:
885:
508:
483:
161:
614:
The data tabulated below shows how bond strengths vary over the periodic table.
427:
requires 101.8 kcal/mol (425.9 kJ/mol). The bond energy of the covalent
1163:
Lone-pair bearing heteroatoms weaken C−H bonds. THF tends to form hydroperoxides
1488:
1444:
1203:
1025:
515:, has the lowest measured bond dissociation energy of only 0.021 kcal/mol.
488:
470:
According to BDE data, the strongest single bonds are Si−F bonds. The BDE for H
384:
192:
117:
1892:
1304:
793:
180:
2279:
2209:
2129:
1845:
1799:
1492:, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "
527:
and is the basis of the usual BDEs. Asymmetric scission of a bond is called
2084:
Gillespie, Ronald J. (July 1998). "Covalent and Ionic
Molecules: Why Are BeF
2060:
1970:
1709:
1575:
1501:
1226:
176:
2287:
2217:
2201:
2143:
Grills D. C.; George M. W. (2001), "Transition metal-noble gas complexes",
1910:
1853:
1676:
1622:
874:
Slightly stronger than C−H bonds, surprisingly low due to stability of C≡O
320:
context. For instance, Blanksby and
Ellison cites the example of ketene (H
523:
Bonds can be broken symmetrically or asymmetrically. The former is called
1326:
929:
816:
770:
698:
432:
416:
412:
54:
2244:
1937:
1755:
Streitwieser, Andrew; Heathcock, Clayton H.; Kosower, Edward M. (2017).
1591:"Critical re-evaluation of the O−H bond dissociation enthalpy in phenol"
2271:
1288:
944:
761:
reactive with almost all organics exothermically by H atom abstraction
2121:
1837:
1668:
1614:
1417:
1394:
1356:
1257:
994:
943:
One of the strongest bonds, large activation energy in production of
907:
649:
428:
89:
70:
16:
Standard enthalpy change when a chemical bond is cleaved by homolysis
370:) and standard redox potentials (ε°) that are measured in solution.
168:
To convert a molar BDE to the energy needed to dissociate the bond
743:
84:
As a typical example, the bond-dissociation energy for one of the
1741:
921:
Stronger than single bonds, weaker than many other double bonds
200:
at 298 K has been measured to high precision and accuracy:
1341:
Akin to allylic C−H bonds. Such bonds show enhanced reactivity
1782:
Perspectives on structure and mechanism in organic chemistry
1371:
Much weaker than C−H bond. Homolytic cleavage occurs when H
103:) is defined as the standard enthalpy change of the process
458:(CH−H) and finally 81 kcal/mol (339 kJ/mol) for
1191:
Conjugating electron-withdrawing groups weaken C−H bonds
474:
Si−F is 152 kcal/mol, almost 50% stronger than the H
808:
O−H bond strength depends strongly on substituent on O
398:) multiplied by the enthalpy change of the reaction EX
1432:
About 2.5 times stronger than a C−C single bond
208:(H−H) = 104.1539(1) kcal/mol or 435.780 kJ/mol.
2030:
Streitwieser A.; Bergman R. G. (19 September 2018).
1955:(3rd ed.). London: Nelson Thornes. p. 7.
1988:
1875:Miller DC, Tarantino KT, Knowles RR (June 2016).
359:→ A•) and one-electron oxidation of B (:B → •B +
1558:Comprehensive handbook of chemical bond energies
531:. For molecular hydrogen, the alternatives are:
382:, the bond-dissociation energy differs from the
1951:Norman, Richard O. C.; Coxon, James M. (2001).
1135:Lone-pair bearing heteroatoms weaken C−H bonds
77:), although the enthalpy change at 298 K (
1726:Bond Dissociation Energies in Simple Molecules
1690:Anslyn, Eric V.; Dougherty, Dennis A. (2006).
553: = 104.2 kcal/mol (see table below)
81:) is also a frequently encountered parameter.
446:−H), 110 kcal/mol (460 kJ/mol) for
65:to give fragments A and B, which are usually
8:
1987:; Nelson, David L.; Cox, Michael M. (2005).
478:C−F bond (110 kcal/mol). The BDE for F
156:= 101.1(4) kcal/mol = 423.0 ± 1.7
1784:(2nd ed.). Hoboken, N.J.: John Wiley.
1103:Tertiary radicals are even more stabilized
958:
616:
1900:
1658:
1303:Such bonds show enhanced reactivity, see
1009:One of the strongest aliphatic C−H bonds
626:Bond-dissociation enthalpy at 298 K
519:Homolytic versus heterolytic dissociation
2233:Journal of the American Chemical Society
1926:Journal of the American Chemical Society
591: = 34.2 kcal/mol (in water) (p
572: = 400.4 kcal/mol (gas phase)
454:−H), 101 kcal/mol (423 kJ/mol) for
147:
143:
123:
119:
113:
109:
99:
95:
1995:(4th ed.). W. H. Freeman. p.
1476:
968:Bond-dissociation energy at 298 K
952:There is great interest, especially in
687:Very strong, rationalizes inertness of
336:have been suggested as an alternative.
1272:Comparable to vinyl radical, uncommon
2056:CRC Handbook of Chemistry and Physics
2032:"Table of Bond Dissociation Energies"
2025:
2023:
1811:
1809:
1694:. Sausalito, CA: University Science.
1640:
1638:
1636:
1634:
1632:
53:. It can be defined as the standard
7:
2092:High Melting Point Solids whereas BF
2034:. University of California, Berkeley
1991:Lehninger Principles of Biochemistry
1551:
1549:
1547:
276:. This is due to the existence of a
220:is similar to the related notion of
1818:The Journal of Physical Chemistry A
1595:The Journal of Physical Chemistry A
1534:The corresponding BDE at 0 K (
852:Strongest bond in neutral molecule
1489:Compendium of Chemical Terminology
1241:Acetylenic radicals are very rare
1072:Secondary radicals are stabilized
663:Strong, but weaker than C−H bonds
212:Definitions and related parameters
14:
2059:(87th ed.). Boca Raton, FL:
1757:Introduction to Organic Chemistry
1734:U.S. National Bureau of Standards
1723:Darwent, B. deB. (January 1970).
1692:Modern physical organic chemistry
784:Slightly stronger than C−H bonds
466:Strongest bonds and weakest bonds
1732:. NSRDS-NBS 31. Washington, DC:
2145:Advances in Inorganic Chemistry
1953:Principles of organic synthesis
1379:thermolysed at >500 °C
2190:Chemistry – A European Journal
2147:, Elsevier, pp. 113–150,
610:Representative bond enthalpies
343:analogue of bond-dissociation
1:
2153:10.1016/s0898-8838(05)52002-6
2102:Journal of Chemical Education
1647:Accounts of Chemical Research
899:Much stronger than C−H bonds
411:For example, dissociation of
349:bond-dissociation free energy
2053:Lide, David R., ed. (2006).
1218:Vinyl radicals are uncommon
712:Strong, nonpolarizable bond
394:, the E–X bond energy is (1/
1881:Topics in Current Chemistry
1541:) is 99.5(5) kcal/mol.
419:bond of a water molecule (H
2329:
1780:Carroll, Felix A. (2010).
222:bond-dissociation enthalpy
1893:10.1007/s41061-016-0030-6
1560:. Boca Raton: CRC Press.
970:
967:
964:
961:
628:
625:
622:
619:
42:) is one measure of the
2308:Chemical bond properties
1494:Bond-dissociation energy
218:bond-dissociation energy
21:bond-dissociation energy
1502:10.1351/goldbook.B00699
298:, and the relationship
2202:10.1002/chem.200801399
1040:Slightly weaker than H
291:is slightly less than
1179:C−H bond α to ketone
263:potential energy well
1985:Lehninger, Albert L.
1151:C−H bond α to ether
1123:C−H bond α to amine
2260:Dalton Transactions
2245:10.1021/ja00514a030
2114:1998JChEd..75..923G
1938:10.1021/ja00212a035
1830:2013JPCA..117.8981K
1607:2005JPCA..109.2647M
1556:Luo, Y. R. (2007).
1060:Isopropyl C−H bond
505:van der Waals force
79:standard conditions
2272:10.1039/C4DT03841J
380:diatomic molecules
183:, measurements of
2266:(13): 5933–5938.
2239:(20): 6046–6056.
2162:978-0-12-023652-7
2122:10.1021/ed075p923
2006:978-0-7167-4339-2
1962:978-0-7487-6162-3
1838:10.1021/jp406200w
1824:(36): 8981–8995.
1791:978-0-470-27610-5
1766:978-93-85998-89-8
1701:978-1-891389-31-3
1669:10.1021/ar020230d
1615:10.1021/jp047148f
1567:978-0-8493-7366-4
1514:gas-phase species
1460:Electron affinity
1455:Ionization energy
1450:Electronegativity
1436:
1435:
954:organic chemistry
950:
949:
796:(an antioxidant)
721:hydrogen fluoride
602:
601:
278:zero-point energy
274:electronic energy
185:chemical kinetics
2320:
2292:
2291:
2255:
2249:
2248:
2228:
2222:
2221:
2196:(8): 1985–1990.
2173:
2167:
2165:
2140:
2134:
2133:
2081:
2075:
2074:
2050:
2044:
2043:
2041:
2039:
2027:
2018:
2017:
2015:
2013:
1994:
1981:
1975:
1974:
1948:
1942:
1941:
1932:(4): 1229–1231.
1921:
1915:
1914:
1904:
1872:
1866:
1865:
1813:
1804:
1803:
1777:
1771:
1770:
1752:
1746:
1745:
1731:
1720:
1714:
1713:
1687:
1681:
1680:
1662:
1642:
1627:
1626:
1586:
1580:
1579:
1553:
1542:
1532:
1526:
1523:
1517:
1510:
1504:
1481:
1420:C≡C triple bond
1091:-Butyl C−H bond
959:
830:typical alcohol
759:hydroxyl radical
617:
536:
535:
425:hydroxyl radical
151:
129:
102:
60:
52:
2328:
2327:
2323:
2322:
2321:
2319:
2318:
2317:
2298:
2297:
2296:
2295:
2257:
2256:
2252:
2230:
2229:
2225:
2187:
2183:
2179:
2175:
2174:
2170:
2163:
2142:
2141:
2137:
2099:
2095:
2091:
2087:
2083:
2082:
2078:
2071:
2052:
2051:
2047:
2037:
2035:
2029:
2028:
2021:
2011:
2009:
2007:
1983:
1982:
1978:
1963:
1950:
1949:
1945:
1923:
1922:
1918:
1874:
1873:
1869:
1815:
1814:
1807:
1792:
1779:
1778:
1774:
1767:
1754:
1753:
1749:
1729:
1722:
1721:
1717:
1702:
1689:
1688:
1684:
1660:10.1.1.616.3043
1644:
1643:
1630:
1601:(11): 2647–55.
1588:
1587:
1583:
1568:
1555:
1554:
1545:
1540:
1533:
1529:
1524:
1520:
1511:
1507:
1482:
1478:
1473:
1441:
1391:
1387:
1378:
1374:
1353:
1349:
1322:
1318:
1314:
1284:
1280:
1253:
1249:
1199:
1175:
1171:
1147:
1143:
1119:
1115:
1111:
1084:
1080:
1056:
1052:
1043:
1021:
1017:
990:
882:
839:carbon monoxide
674:
612:
597:
583:
564:
545:
521:
514:
502:
494:
481:
477:
473:
468:
453:
445:
422:
402:
392:
376:
369:
347:, known as the
334:force constants
331:
327:
323:
315:
311:
304:
297:
290:
283:
272:, known as the
271:
257:
249:
242:
234:
214:
207:
199:
160:= 4.40(2)
149:
145:
141:
139:
125:
121:
115:
111:
107:
101:
97:
93:
67:radical species
58:
50:
34:
17:
12:
11:
5:
2326:
2324:
2316:
2315:
2313:Binding energy
2310:
2300:
2299:
2294:
2293:
2250:
2223:
2185:
2181:
2177:
2168:
2161:
2135:
2097:
2093:
2089:
2085:
2076:
2069:
2045:
2019:
2005:
1976:
1961:
1943:
1916:
1867:
1805:
1790:
1772:
1765:
1747:
1715:
1700:
1682:
1628:
1581:
1566:
1543:
1538:
1527:
1518:
1505:
1475:
1474:
1472:
1469:
1468:
1467:
1465:Lattice energy
1462:
1457:
1452:
1447:
1440:
1437:
1434:
1433:
1430:
1427:
1424:
1421:
1415:
1411:
1410:
1407:
1404:
1401:
1398:
1392:
1389:
1385:
1381:
1380:
1376:
1372:
1369:
1366:
1363:
1360:
1354:
1351:
1347:
1343:
1342:
1339:
1336:
1333:
1330:
1324:
1320:
1316:
1312:
1308:
1307:
1301:
1298:
1295:
1292:
1286:
1282:
1278:
1274:
1273:
1270:
1267:
1264:
1261:
1255:
1251:
1247:
1243:
1242:
1239:
1236:
1233:
1230:
1224:
1220:
1219:
1216:
1213:
1210:
1207:
1201:
1197:
1193:
1192:
1189:
1186:
1183:
1180:
1177:
1173:
1169:
1165:
1164:
1161:
1158:
1155:
1152:
1149:
1145:
1141:
1137:
1136:
1133:
1130:
1127:
1124:
1121:
1117:
1113:
1109:
1105:
1104:
1101:
1098:
1095:
1092:
1086:
1082:
1078:
1074:
1073:
1070:
1067:
1064:
1061:
1058:
1054:
1050:
1046:
1045:
1041:
1038:
1035:
1032:
1029:
1023:
1019:
1015:
1011:
1010:
1007:
1004:
1001:
998:
992:
988:
984:
983:
980:
977:
973:
972:
969:
966:
963:
948:
947:
941:
938:
935:
932:
927:
923:
922:
919:
916:
913:
910:
905:
901:
900:
897:
894:
891:
888:
883:
880:
876:
875:
872:
869:
866:
863:
861:carbon dioxide
858:
854:
853:
850:
847:
844:
841:
836:
832:
831:
828:
825:
822:
819:
814:
810:
809:
806:
803:
800:
797:
790:
786:
785:
782:
779:
776:
773:
767:
763:
762:
755:
752:
749:
746:
740:
736:
735:
732:
729:
726:
723:
718:
714:
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710:
707:
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685:
682:
679:
676:
672:
669:
665:
664:
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658:
655:
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642:
641:
638:
635:
631:
630:
627:
624:
621:
611:
608:
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603:
600:
599:
595:
585:
581:
578:
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573:
566:
562:
559:
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547:
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520:
517:
512:
500:
492:
479:
475:
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451:
443:
420:
400:
390:
375:
372:
367:
329:
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321:
313:
309:
302:
295:
288:
281:
269:
255:
247:
240:
232:
213:
210:
205:
197:
191:, and various
166:
165:
137:
131:
61:is cleaved by
32:
15:
13:
10:
9:
6:
4:
3:
2:
2325:
2314:
2311:
2309:
2306:
2305:
2303:
2289:
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2234:
2227:
2224:
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2207:
2203:
2199:
2195:
2191:
2188:Case Study".
2172:
2169:
2164:
2158:
2154:
2150:
2146:
2139:
2136:
2131:
2127:
2123:
2119:
2115:
2111:
2107:
2103:
2100:Are Gases?".
2080:
2077:
2072:
2070:0-8493-0487-3
2066:
2062:
2058:
2057:
2049:
2046:
2033:
2026:
2024:
2020:
2008:
2002:
1998:
1993:
1992:
1986:
1980:
1977:
1972:
1968:
1964:
1958:
1954:
1947:
1944:
1939:
1935:
1931:
1927:
1920:
1917:
1912:
1908:
1903:
1898:
1894:
1890:
1886:
1882:
1878:
1871:
1868:
1863:
1859:
1855:
1851:
1847:
1843:
1839:
1835:
1831:
1827:
1823:
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1812:
1810:
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1797:
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1703:
1697:
1693:
1686:
1683:
1678:
1674:
1670:
1666:
1661:
1656:
1653:(4): 255–63.
1652:
1648:
1641:
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1637:
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1228:
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1190:
1187:
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1139:
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1131:
1128:
1125:
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1107:
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1102:
1099:
1096:
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1075:
1071:
1068:
1065:
1062:
1059:
1048:
1047:
1039:
1036:
1033:
1030:
1027:
1024:
1013:
1012:
1008:
1005:
1002:
999:
996:
993:
986:
985:
981:
978:
975:
974:
960:
957:
955:
946:
942:
939:
936:
933:
931:
928:
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917:
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895:
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829:
826:
823:
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815:
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798:
795:
791:
788:
787:
783:
780:
777:
774:
772:
768:
765:
764:
760:
757:Very strong,
756:
753:
750:
747:
745:
741:
738:
737:
733:
730:
727:
724:
722:
719:
716:
715:
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708:
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618:
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579:
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548:
541:
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366:
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358:
354:
350:
346:
342:
337:
335:
317:
308:
301:
294:
287:
279:
275:
268:
265:of the bond,
264:
259:
253:
246:
238:
231:
227:
226:bond enthalpy
223:
219:
211:
209:
203:
194:
190:
186:
182:
178:
173:
171:
163:
159:
155:
135:
132:
127:
106:
105:
104:
91:
87:
82:
80:
76:
75:absolute zero
72:
68:
64:
56:
49:
48:chemical bond
45:
41:
40:
35:
31:
26:
22:
2263:
2259:
2253:
2236:
2232:
2226:
2193:
2189:
2171:
2144:
2138:
2105:
2101:
2079:
2054:
2048:
2036:. Retrieved
2010:. Retrieved
1990:
1979:
1952:
1946:
1929:
1925:
1919:
1884:
1880:
1870:
1821:
1817:
1781:
1775:
1756:
1750:
1725:
1718:
1691:
1685:
1650:
1646:
1598:
1594:
1584:
1557:
1535:
1530:
1521:
1513:
1508:
1487:
1479:
1088:
951:
886:formaldehyde
734:Very strong
613:
605:
592:
588:
577:Asymmetric:
569:
558:Asymmetric:
550:
522:
509:helium dimer
497:
484:deprotection
469:
459:
455:
447:
439:
437:
410:
405:
399:
395:
389:
383:
377:
364:
360:
356:
352:
348:
344:
340:
338:
318:
306:
299:
292:
285:
273:
266:
260:
251:
244:
236:
229:
225:
221:
217:
215:
201:
193:calorimetric
174:
170:per molecule
169:
167:
153:
133:
83:
57:change when
38:
37:
29:
28:
24:
20:
18:
1445:Bond energy
976:(kcal/mol)
648:in typical
634:(kcal/mol)
546:→ 2 H
539:Symmetric:
529:heterolysis
489:diacetylene
385:bond energy
378:Except for
374:Bond energy
341:free energy
189:equilibrium
164:(per bond).
2302:Categories
2108:(7): 923.
1471:References
1368:3.60–3.90
1305:drying oil
1227:Acetylenic
982:(eV/bond)
794:tocopherol
660:3.60–3.90
640:(eV/bond)
181:photolysis
2280:1477-9234
2210:0947-6539
2130:0021-9584
2061:CRC Press
1887:(3): 30.
1846:1089-5639
1800:286483846
1655:CiteSeerX
1397:C=C bond
1359:C−C bond
1329:C−H bond
1291:C−H bond
1260:C−H bond
1229:C−H bond
1206:C−H bond
1028:C−H bond
997:C−H bond
979:(kJ/mol)
637:(kJ/mol)
525:homolysis
216:The term
177:pyrolysis
86:C−H bonds
63:homolysis
2288:25697077
2218:19021178
2038:13 March
1971:48595804
1911:27573270
1862:11884042
1854:23927609
1742:70602101
1710:55600610
1677:12693923
1623:16833571
1576:76961295
1439:See also
1365:347–377
1327:Benzylic
971:Comment
930:nitrogen
817:methanol
771:methanol
699:hydrogen
657:347–377
629:Comment
598:= 25.1)
584:→ H + H
565:→ H + H
345:enthalpy
250:(R−H) ≈
55:enthalpy
44:strength
2110:Bibcode
2096:and SiF
2088:and AlF
2012:May 20,
1902:5107260
1826:Bibcode
1603:Bibcode
1289:Allylic
1172:C(=O)CH
945:ammonia
316:holds.
116:−H →
2286:
2278:
2216:
2208:
2159:
2128:
2067:
2003:
1969:
1959:
1909:
1899:
1860:
1852:
1844:
1798:
1788:
1763:
1740:
1708:
1698:
1675:
1657:
1621:
1574:
1564:
1429:~10.0
1418:Alkyne
1414:HC≡CH
1395:Alkene
1362:83–90
1357:Alkane
1338:3.907
1300:3.856
1269:4.902
1258:Phenyl
1238:5.763
1223:HCC−H
1215:4.809
1188:4.163
1160:3.990
1148:OCH−H
1132:3.949
1100:4.187
1069:4.293
1037:4.384
1006:4.550
995:Methyl
908:oxygen
849:11.16
689:Teflon
654:83–90
650:alkane
404:→ E +
158:kJ/mol
90:ethane
1858:S2CID
1730:(PDF)
1484:IUPAC
1426:~960
1423:~230
1406:~7.4
1403:~710
1400:~170
1204:Vinyl
1200:CH−H
1094:96.5
1057:CH−H
1026:Ethyl
965:Bond
962:Bond
940:9.79
918:5.15
896:7.75
871:5.51
857:O=CO
846:1077
827:3.99
805:3.35
792:in α-
781:4.56
754:5.15
744:water
731:5.90
709:4.52
684:4.99
671:in CH
623:Bond
620:Bond
152:) = Δ
46:of a
36:, or
2284:PMID
2276:ISSN
2214:PMID
2206:ISSN
2157:ISBN
2126:ISSN
2065:ISBN
2040:2019
2014:2016
2001:ISBN
1967:OCLC
1957:ISBN
1907:PMID
1850:PMID
1842:ISSN
1796:OCLC
1786:ISBN
1761:ISBN
1738:LCCN
1706:OCLC
1696:ISBN
1673:PMID
1619:PMID
1572:OCLC
1562:ISBN
1388:C=CH
1375:C−CH
1350:C−CH
1335:377
1297:372
1281:CHCH
1266:473
1263:113
1235:556
1232:133
1212:464
1209:111
1185:402
1157:385
1129:381
1097:404
1085:C−H
1066:414
1044:C−H
1034:423
1031:101
1003:439
1000:105
991:C−H
937:945
934:226
926:N≡N
915:498
912:119
904:O=O
893:748
890:179
879:O=CH
868:532
865:127
843:257
835:C≡O
824:385
813:C-O
802:323
789:O−H
778:440
775:105
766:O−H
751:497
748:119
739:O−H
728:569
725:136
717:H−F
706:431
703:103
695:H−H
681:481
678:115
668:C−F
645:C−C
511:, He
499:(CO)
328:C=CH
224:(or
187:and
128:+ H•
19:The
2268:doi
2241:doi
2237:101
2198:doi
2149:doi
2118:doi
1934:doi
1930:110
1897:PMC
1889:doi
1885:374
1834:doi
1822:117
1665:doi
1611:doi
1599:109
1498:doi
1496:".
1332:90
1323:−H
1294:89
1285:−H
1254:−H
1182:96
1176:−H
1154:92
1140:(CH
1126:91
1120:−H
1116:NCH
1108:(CH
1077:(CH
1063:99
1049:(CH
1022:−H
821:92
799:77
769:in
742:in
487:of
450:(CH
442:(CH
312:− ε
256:298
241:298
206:298
179:or
138:298
88:in
59:A−B
51:A−B
39:DH°
25:BDE
2304::
2282:.
2274:.
2264:44
2262:.
2235:.
2212:.
2204:.
2194:15
2192:.
2186:20
2182:20
2180:@C
2155:,
2124:.
2116:.
2106:75
2104:.
2063:.
2022:^
1999:.
1997:48
1965:.
1928:.
1905:.
1895:.
1883:.
1879:.
1856:.
1848:.
1840:.
1832:.
1820:.
1808:^
1794:.
1736:.
1704:.
1671:.
1663:.
1651:36
1649:.
1631:^
1617:.
1609:.
1597:.
1593:.
1570:.
1546:^
1486:,
1319:CH
1277:CH
1196:CH
1168:CH
675:F
589:G°
570:H°
551:H°
507:,
413:HO
305:=
252:DH
237:DH
202:DH
162:eV
154:H°
150:−H
146:CH
142:CH
134:DH
122:CH
118:CH
112:CH
108:CH
27:,
2290:.
2270::
2247:.
2243::
2220:.
2200::
2184:H
2178:2
2166:.
2151::
2132:.
2120::
2112::
2098:4
2094:3
2090:3
2086:2
2073:.
2042:.
2016:.
1973:.
1940:.
1936::
1913:.
1891::
1864:.
1836::
1828::
1802:.
1769:.
1744:.
1712:.
1679:.
1667::
1625:.
1613::
1605::
1578:.
1539:0
1536:D
1500::
1390:2
1386:2
1384:H
1377:3
1373:3
1352:3
1348:3
1346:H
1321:2
1317:5
1315:H
1313:6
1311:C
1283:2
1279:2
1252:5
1250:H
1248:6
1246:C
1198:2
1174:2
1170:3
1146:3
1144:)
1142:2
1118:2
1114:2
1112:)
1110:3
1089:t
1083:3
1081:)
1079:3
1055:2
1053:)
1051:3
1042:3
1020:5
1018:H
1016:2
1014:C
989:3
987:H
881:2
673:3
596:a
593:K
587:Δ
582:2
580:H
568:Δ
563:2
561:H
549:Δ
544:2
542:H
513:2
501:5
493:2
480:3
476:3
472:3
460:D
456:D
452:2
448:D
444:3
440:D
433:H
431:−
429:O
421:2
417:H
415:−
406:n
401:n
396:n
391:n
368:a
365:K
361:e
357:e
353:G
330:2
326:2
322:2
314:0
310:e
307:D
303:0
300:D
296:e
293:D
289:0
286:D
282:0
280:ε
270:e
267:D
254:°
248:0
245:D
239:°
233:0
230:D
204:°
198:2
148:2
144:3
140:(
136:°
130:,
126:•
124:2
120:3
114:2
110:3
100:6
98:H
96:2
94:C
92:(
73:(
71:K
33:0
30:D
23:(
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.