Easy Temperature and Kinetic Throey Problem

AI Thread Summary
The discussion revolves around calculating the final pressure of a gas after it is compressed and heated. The user initially attempted to use the ideal gas law (pV=nRT) but struggled with the calculations for the number of moles (n). They realized the need to convert the temperature from Celsius to Kelvin for accurate results. The conversation suggests using the relationship pV/T = constant, which applies to both initial and final states, to derive two equations with the known variables. Ultimately, the focus is on correctly applying the gas laws to find the final pressure after the gas undergoes compression and temperature increase.
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If 2.4m^3 of a gas initially at STP is compressed to 1.6m^3 and its temperature is raised to 30degreesC, what is the final pressure?

I thought this would be a easy one but my answers are coming out and don't look right.

I used pV=nRT

p=1.6m^3
V=2.4m^3
R=8.31J(mol*k) --- universal gas constant
T=30degreesC

So I plugged everything into the equation pV=nRT and solved for n and got .015403, it didnt look right so I converted 30degreesC to K (which equals 303.15K) then solved for n again and got .00154, which I am sure is also wrong.

Am I using the wrong equation?? There was only a few to choose from in the book:

pV/T=Constant, pV=nRT, pV/T=NKsubB

Please Help thanks
 
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if you look at what you are given you have Po, Vo, To. Then we know it is compressed and the temp raises so we know T and V after. We have to solve for P. from the equations below there's one that uses those 3 variables.
 
Im assuming pV/T=constant, because the other two deal with molecules.

so p(2.4m^3)/30=1.6m^3?
 
PV/T = constant (nK) and that works for both initial and final. Now you'll have two equations with two unknowns, Tfinal and constant

you also know initial pressure, initial volume, and initial temperature so you can find what the constant equals
 
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