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I have a question about Optics and how this links to burning fuels in a combustion reaction.

If I have hexane, the following reaction occurs:

hexane + oxygen $\rightarrow$ carbon dioxide + water vapour

Now, I have a question. Why don't we tend to see any water being formed when we burn methane on a gas cooker?

This is only because the same equation can also be applied to methane in our cookers:

methane + oxygen $\rightarrow$ carbon dioxide + water vapour

I tried this earlier while preparing my food and it turns out I don't see any, even though I am burning the fuel.

Qmechanic
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user55213
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2 Answers2

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The air in the kitchen is warm enough and dry enough that the water vapor isn't condensing. If you want to see it, take a pan and fill it will ice water, then put it over the flame. You'll see the water vapor condensing on the outside of the pot.

zeta-band
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Because the water vapour/$CO_2$ mixture is very hot. Then it mixes with the surrounding air and dilutes too much to condense. This why you can't "see" it.

But hold a really cold pan in the flame and initially you'll see water condense onto the surface of the pan. Then the pan heats up and the condensation evaporates again.

Gert
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