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Topic: Density of a gas mixture  (Read 6569 times)

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Offline Kuahji

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Density of a gas mixture
« on: December 03, 2007, 09:11:17 AM »
The question is, "What is the density (in grams per liter) of a gas mixture that contains 27.0% F2 & 73.0% He by volume at 714 mm Hg & 27.5 C?"

The first thing I was to to convert the mm Hg into atm & got .939 atm & then I convert the degrees in Celsius to Kelvin & got 300.6 K.  But this is where I seem to be stuck.  I have two variables.  I don't know the volume & I don't know the number of moles.  How can I solve the problem?

Offline Borek

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Re: Density of a gas mixture
« Reply #1 on: December 03, 2007, 09:15:19 AM »
While it can be done using more general approach, start assuming you have exactly 1L of the mixture.
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Offline AWK

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Re: Density of a gas mixture
« Reply #2 on: December 03, 2007, 09:17:17 AM »
pM=dRT
M=0.27x38 + 0.73x4
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Offline Kuahji

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Re: Density of a gas mixture
« Reply #3 on: December 03, 2007, 09:24:13 AM »
pM=dRT
M=0.27x38 + 0.73x4
Ok thanks, this was a big help.  I tried this the first time around, but couldn't figure out how to cancel the moles, clearly though that is a big M & not a little m, which would make all the difference.  Thanks  8).

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