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What's the gas expansion ratio for ethanol? Answered

At normal atmospheric pressure. Don't need too precise a figure, nearest 50 will do.

Surprisingly difficult information to find...

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user
lemonie (author)2010-01-18

What do you mean? Vapour pressure or volume gas per ml liquid?
I'll assume you want "how much gas do I get at the boiling point?".
Molar volume of a gas at 25oC is ~ 25 L, which is 46g, or ~58ml.

Treating it as an ideal gas, V=RT/P
At boiling point and atmospheric pressure V ~29 Litres gas for 58ml liquid, or about 500x liquid volume.

L

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user
SolarFlower_org (author)lemonie2010-01-18

That is what I was after, thanks.

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user
lemonie (author)SolarFlower_org2010-01-18

Hooray!

The idea gas equation can be found here (of many places), I guess you'll be wanting pressures at some point?
en.wikipedia.org/wiki/Molar_volume

L

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SolarFlower_org (author)lemonie2010-01-18

I had a look at that, but as is my way now of outsourcing all my thinking to the internet: wolfram alpha.

Pressures shouldn't be an issue.

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