Bond Dissociation Enthalpies

Bond dissociation enthalpies
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Bond Dissociation Enthalpies EH(A-B)

 

Average bond dissociation enthalpies (energies) for bonds A-B at 298 K and 1 atm pressure are given. The enthalpy of each bond is the mean bond dissociation enthalpy, or simply the bond enthalpy EH(A-B). This is the average value of bond dissociation enthalpies of the A-B bond in a series of different compounds.

A standard enthalpies of formation table can be found in the post "Standard Enthalpies of Formation of Inorganic Compounds".

 

Table 1: Single Bond Dissociation Enthalpies EH(A-B) kJ/mol

T = 298.15K and P = 1 atm
Bond EH(A-B) Length (nm)
Br-Br 193 0.228
Br-H 366 0.141
Br-Cl 219  
Cl-Cl 243 0.199
Cl-H 432 0.127
Cl-N 200  
Cl-O 203  
Cl-F 254  
F-F 153 0.142
F-H 563 0.092
F-N 270  
F-O 185  
I-I 151 0.267
I-Cl 210  
I-C 240  
H-I 299 0.161
H-H 436 0.074
H-Si 318 0.148
H-N 391 0.101
H-P 321 0.144
H-O 463 0.096
H-S 399 0.134
H-C* 413 0.108
N-N 161 0.145
N=N 410 0.120
N≡N 945 0.110
O-O (in H2O2) 144 0.148
O-O (in O3) 302 0.128
O=O 497 0.121
O-Si 466 0.161
P-P (in P4) 198 0.221
P=P (in P2) 485 0.189
C-C* 348 0.154
C=C* 612 0.134

* Average bond enthalpies

References

  1. CRC Handbook of Chemistry and Physics, 52nd edition, The Chemical Rubber Co., (1971)
  2. David W. Oxtoby, H.P. Gillis, Alan Campion, “Principles of Modern Chemistry”, Sixth Edition, Thomson Brooks/Cole, 2008
  3. Steven S. Zumdahl, “Chemical Principles”  6th Edition, Houghton Mifflin Company, 2009
  4. Linus Pauling, "The Nature of the Chemical Bond", 3rd Edition, Cornell University Press, 1960

Key Terms

bond enthalpies, average bond enthalpy, bond lenghts,

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