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Q & A: H2 +O2

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Most recent answer: 10/22/2007
Q:
an you mix hydrogen + oxygen WITHOUT an explosion or carbon dioxide?
- jack (age 14)
Broxbourne, England
A:
What's the CO2 doing in there? It's not a product of H2 and O2 combining, which just gives water (2H2+O2->2H2O). Was it supposed to act to absorb energy to prevent the mixed H2 and O2 from exploding? You can certainly use inert gases, such as argon, for that purpose. If I remember right, some vendors will supply H2 mixed with Ar so that it is dilute enough not to form an explosive mixture with air.

Mike W.

Hydrogen and oxygen need some kind of trigger in order to explode, such as a spark or an open flame. It could be that spontaneous reactions can generate enough heat to trigger an explosion. Grain elevators out here in the midwest can explode because of the flammability of the grains and the heat that is built up (but this comes from biological processes -- fermenting bacteria generate heat which is trapped in the grain and can get the temperature over the ignition point).

H2 + O2 mixed together without some kind of diluting agent (like argon or nitrogen) sounds dangerous and I woudn't stand nearby even if there are no sparks or flames.

Tom

(published on 10/22/2007)

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