Thermochemistry of reductions caused by lithium aluminium hydride. Part 3.—The C-halogen bond dissociation energies in ethyl iodide and ethyl bromide

1965 ◽  
Vol 61 (0) ◽  
pp. 225-229 ◽  
Author(s):  
S. J. Ashcroft ◽  
A. S. Carson ◽  
W. Carter ◽  
P. G. Laye
Keyword(s):  
Halogen Bond ◽  
Ethyl Bromide ◽  
Ethyl Iodide ◽  
Bond Dissociation Energies ◽  
Lithium Aluminium Hydride ◽  
Bond Dissociation ◽  
Dissociation Energies ◽  
Lithium Aluminium

A study of the C 2 H 4 +HCl=C 2 H 5 Cl and C 2 H 4 +HBr=C 2 H 5 Br equilibria

1953 ◽  
Vol 216 (1126) ◽  
pp. 361-374 ◽  
Keyword(s):  
Equilibrium Constants ◽  
Entropy Change ◽  
Heat Of Formation ◽  
Ethyl Chloride ◽  
Ethyl Bromide ◽  
Bond Dissociation Energies ◽  
Kcal Mole ◽  
Bond Dissociation ◽  
Dissociation Energies ◽  
Heat Of Dissociation

The equilibrium constants of the two reactions C 2 H 4 + H X = C 2 H 5 X , where X = Cl or Br, have been measured for X = Cl from 449 to 491° K, and for X = Br from 515 to 573° K, The methods of preparing and purifying the substances used, of carrying out the analyses and of determining the equilibrium constants have been described. The results for the ethyl chloride equilibrium were combined with calculations of the entropy change using Gordon & Giauque’s barrier height in ethyl chloride of 3700 cal/mole to obtain a value for the heat content change. The value for this, corrected to 298° K, is 17·1 kcal/mole. This leads to a heat of formation of ethyl chloride of – 26·7 and a heat of dissociation of the C—Cl bond in ethyl chloride of 80·9 kcal/mole. For the ethyl bromide equilibrium, the entropy change was calculated using barrier heights in ethyl bromide of 3000, 4000 and 5000 cal/mole. Using the entropy changes calculated it was concluded that the heat of reaction, corrected to 298° K, is within 0·3 kcal/mole of 19·1. This leads to a heat of formation of ethyl bromide of – 15·3 and a heat of dissociation of the C—Br bond in ethyl bromide of 67·2 kcal/mole. The two bond dissociation energies have been incorporated in the recent tables of Mortimer, Pritchard & Skinner listing such energies. The significance of the values for the bond dissociation energies in the series of RX molecules, where R = Me, Et, n-Pr, n-Bu, iso-Pr and tert.-Bu , and X = H, Cl and Br have been discussed.

scholarly journals Experimental bond dissociation energies of benzylpyridinium thermometer ions determined by threshold-CID and RRKM modeling

2017 ◽  
Vol 417 ◽  
pp. 69-75 ◽  
Author(s):  
David Gatineau ◽  
Antony Memboeuf ◽  
Anne Milet ◽  
Richard B. Cole ◽  
Héloïse Dossmann ◽  
...  
Keyword(s):  
Bond Dissociation Energies ◽  
Bond Dissociation ◽  
Dissociation Energies ◽  
Thermometer Ions
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