Physical Chemistry 3: — Chemical Kinetics — - Christian-Albrechts ...

2.1 Definitions and conventions 13
I
Figure 2.2: Reactions in the H 2 /O 2 system.
I Rate equations for the H 2 /O 2 system: Assuming that we know the reaction mechanism
(i.e., all elementary reactions contributing), we can write down the rate equations
for all species. Doing so, we obtain a set of coupled non-linear differential equations
(DE’s) which can be solved usually only numerically, if we want to describe the
net reaction:
[H]
[OH]
[O]
= − 1 [H] [O 2 ]+ 2 [O] [H 2 ]+ 3 [OH] [H 2 ] − 4 [H] [O 2 ][M] (2.23)
− 5 [H] [HO 2 ] − 6 [H] [HO 2 ]+
= 1 [H] [O 2 ]+ 2 [O] [H 2 ] − 3 [OH] [H 2 ]+2 6 [H] [HO 2 ] (2.24)
− 7 [OH] [HO 2 ] − 2 8 [OH] 2 [M]
+ (2.25)
= (2.26)