| Reaction Type |
Log10A |
Ea (Kcal/mole) |
ΔHr (Kcal/mole) @298 K |
I. Unimolecular Reactions,
k= A exp(-Ea/RT), s-1 |
|
|
|
| a. Simple Fission Reactions |
|
|
|
| CH4 < = = > CH3 +H |
16.0 |
105 |
105 |
| Recommendation |
15.5 |
ΔHr |
|
| b. Complex Fission Reactions |
|
|
|
| b1. Radical Fissions |
|
|
|
| C2H5 < = => C2H4 +H |
13.6 |
40.9 |
38.7 |
| Recommendation |
13.0 |
ΔHr |
|
| CH3CO <= = > CH3 + CO |
12.4 |
16.7 |
14.2 |
| Recommendation |
13.0 |
ΔHr +5 |
|
| b2. Molecular Fissions |
|
|
|
| Three and Four Center Eliminations |
|
|
|
| C2H5 Cl < = = > C2H4 + HCl |
13.5 |
56.6 |
20.2 |
| Recommendation |
13.5 |
1/3( sum of bond energies broken)
or ΔHr + 25 |
|
| b3. Isomerization Reactions |
|
|
|
| b3.1 Cis- Trans Isomerization |
|
|
|
| CHCl=CHCl cis < = = > trans |
13.8 |
63.0 |
0.0 |
| Recommendation |
13.0 |
Pi-bond energy + 4.0 |
|
| b3.2 Atom Migrations |
|
|
|
| 1-C3H7 <= = > 2-C3H7 |
12.4 |
34.0 |
0.0 |
| Recommendation |
13.0 |
35 for 1,2 shift
25 for 1,3 shift |
|
| b3.3 Cyclizations & Decyclizations |
15.2 |
65.0 |
-27.6 |
| Recommendation |
15.0 |
60.0 |
|
| Reaction Type |
Log10A |
Ea (Kcal/mole) |
DHr (Kcal/mole) @298 K |
II Bimolecular Reactions
K= AT2exp(Ea/RT)
cm3/mol-sec |
|
|
|
| a. Atom Metathesis Reactions |
|
|
|
| H + CH4 < = = > CH3 + H2 |
8.85 |
11.6 |
0.0 |
| Recommendation |
8.50 |
FA x FC see below |
|
| CH3 + C2H6 < = = > CH4 + C2H5 |
6.55 |
10.8 |
-4.7 |
| Recommendation |
7.00 |
FA x FC see below |
|
| Reaction A + BC , = = > AB + C |
|
|
|
| Group or Atom |
F |
|
|
| H |
3.00 |
|
|
| Cl |
0.57 |
|
|
| O |
2.15 |
|
|
| OH |
1.30 |
|
|
| NH2 |
1.30 |
|
|
| HO2 |
1.70 |
|
|
| CHO |
1.55 |
|
|
| CH3 |
3.50 |
|
|
| C2H5 |
2.85 |
|
|
| b. Radical-radical Metathesis |
|
|
|
| C2H3 + H < = = > C2H2 +H2 |
8.35 |
0.0 |
-66.3 |
| Recommendation |
8.00 |
0.0 |
|
| c. Molecule-Molecule Metathesis |
|
|
|
| C2H4 + C2H4 < = = > C2H3 + C2H5 |
9.15 |
72.0 |
70.0 |
| Recommendation: Use microscopic reversibility. |
|
|
|
III. Complex Bimolecular Reactions
k= Aexp(Ea/RT)
cm3/mol-sec |
|
|
|
| CH3 + O2<= = > CH2O + OH |
13.7 |
34.6 |
-53.0 |
| Recommendation: None. |
|
|
|
