# Chemistry

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Determine the density of methane (CH4) in g/L at 27.8oC and 1.1 atm.

• Chemistry - ,

The general gas formula of PV = nRT can be modified to
P*molar mass = density*R*T

• Chemistry - ,

So I have gotten 2 different answers. I used V=nRT/P to get the volume. Which was 24.7. Then I used D=M/V and divided 16.042/24.7 to get .65g/L

Is that right?

• Chemistry - ,

no. If you obtained two different answers why did you pick that one? You know something must be wrong. How did you get V = 24.7 L. If I plug those numbers into V =nRT/P I don't get that. But I do obtain a number that agrees with the formula I gave you.

• Chemistry - ,

V=nRT/P I used (1)(.0821)(300.8)/1=24.7

• Chemistry - ,

Two points.
If T is to 4 places I would use R as 0.08205 although that won't make much difference.
The other one makes more difference. P is 1.1 atm in the problem and not 1.

• Chemistry - ,

Yes, thank you for catching that. So with the corrections (except I kept R as .0821) I got (1)(.0821)(300.8)/1.1=22.45. Then 16.042/22.45=0.71g/L

Is it now correct? I appreciate all your help!!!

• Chemistry - ,

Yes. If that 1.1 is 1.1 and not 1.10 atm, then 0.71 is right. If it is 1.10 you should have one more place in your answer.

• Chemistry - ,

THANK YOU!!!