Capt Chaos
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H2O2 Decomp to O2 - Volume Calc?
Okay, I'm tired and need a peer review/conflict resolution.
What did I do wrong below?
40 volume peroxide is only supposed to produce 40 x 250ml = 10 L, not 21. I've even done the experiment and it's more like 10 L (maybe a little less).
Definitely not 21 L.
It's probably something obvious but I'm bleary. Have to iron this out tomorrow, so would love some input. I'll revisit tomorrow.
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Poppy
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It's by definition, the volume of oxygen gas the peroxide would release if decomposed completly at room temperature. Thus 40 volumes would mean a
250mL bottle would release 40x250mL oxygen gas, thats 10L <_<
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Neil
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Looks like you mixed up O and O2 --> ~20L of O vs ~10L O2
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Capt Chaos
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I am not sure I follow.
O2 is the correct in the formula and most of the references are fairly clear, stating that the volume rating is based on oxygen (O2).
It would seem unusual to assign a volume to just 'O'. Would O have a volume in this context and if it did, would it be likely to be half of O2?
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unionised
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Quote: Originally posted by Poppy  | | It's by definition, the volume of oxygen gas the peroxide would release if decomposed completly at room temperature. Thus 40 volumes would mean a
250mL bottle would release 40x250mL oxygen gas, thats 10L <_< |
No it isn't.
It's the volume you get if you add it to excess of an oxidant - typically KMnO4.
That way you get twice as much oxygen given off so your product looks twice as good.
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