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So I was curious regarding a simple chemical equation :

$$\ce{2 H2 + O2 -> 2 H2O}$$

You add heat to the system (i.e fire) and you get water vapor.

I'm curious of understanding the mechanism, which I'm sure at this point has been well studied.

Suppose I keep track of the location of each one of these atoms, and the energy nearby - my anticipation is that the reaction occurs when the atoms get close enough and there is sufficient energy present to conduct the reaction. Is there any way to summarize this critical point of water creation mathematically in this framework (i.e the combination of atoms being close enough and sufficient energy will make this reaction take place) - or is there a superior way?

Does anyone have any insight/publications that can help me understand the steps of water synthesis via reaction mechanism?

Mithoron
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Vogtster
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    Math is not about summarizing things (that's creative writing). Math is about more specific questions, which often start with "how many". – Ivan Neretin May 29 '19 at 18:29
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    It seems to me your post is an example of what happens when asker doesn't know proper terminology. If you want reaction mechanism, or chemical reaction model or something elese, then make up your mind and edit the question. – Mithoron May 29 '19 at 18:36
  • @Mithoron reaction mechanism looks like what im interested in. I'll edit the question. Thanks - I'm from the mathematics community so not a very good chemist. – Vogtster May 29 '19 at 19:29

1 Answers1

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Martin - マーチン has given excellent answer here. I'll give here an supporting review article for your benefit, which also gives some mathematical overview:

  • Louis S. Kassel, “The Mechanism of the Combustion of Hydrogen,” Chem. Rev. 1937, 21(2), 331–345 (DOI: 10.1021/cr60069a010).

Overall, mechanism can be summerized as follows: \begin{align} \ce{H2 + \text{heat} &-> 2 H^.}\\ \ce{H^. + O2 &-> HO-O^.}\\ \ce{HO-O^. + H2 &-> HO-OH + H^.}\\ \ce{H^. + HO-OH &-> H2O + HO^.}\\ \ce{HO^. + H2 &-> H2O + H^.} \end{align}

The propagation would continue with having $\ce{H^.}$ at the end and the presence of excess $\ce{O2}$.

Martin - マーチン
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Mathew Mahindaratne
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    It is somewhat interesting that the mechanism you outline is not quite that posted by Martin- any comments on which one is closer to the truth, or when differences might be seen? – Buck Thorn May 30 '19 at 08:25
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    @Night Writer: See attached review paper. There are a lot of hand waiving arguments but this come closed to the real one, I guess. – Mathew Mahindaratne May 30 '19 at 15:58
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    to me it seems unlikely that H atoms are formed in this way as the energy involved is huge (436 kJ/mole) More likely is that $\ce{H2 + O2 \to OH\cdot}$ is the first step 72 kJ/mole and H atoms produced by the propagation step. Also peroxide is not a major a component except possibly at the third explosion limit since peroxide has a retarding effect on the reaction replacing reactive OH with less reactive $\ce{HO2}$ via $\ce{OH + H2O2 \to H2O + HO2}$ – porphyrin May 31 '19 at 08:53
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    I have added the scheme to the question referred to in the first line of your answer. – porphyrin May 31 '19 at 09:27