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Topic: Pressure/Volume- gases  (Read 5800 times)

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Offline nikita

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Pressure/Volume- gases
« on: October 15, 2008, 12:59:07 PM »
I have attempted this problem numerous times and keep getting the same answer, which, apparently, is the wrong one.  It is just a gas question with T2 as the unknown.

The volume of a gas is 36.0 mL at 10C and 4.50 atm.  At what temperature C will the gas have a pressure of 3.50 atm and a volume of 85.0 mL?

I used the formula P1V1/T1 = P2V2/T2
and inserted the following:
(4.50x.036L/10C) = (3.50x.085L/T2)

i rearranged the variables to solve for T2 and have gotten 18.4 C every time.  What am i doing wrong?


Offline macman104

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Re: Pressure/Volume- gases
« Reply #1 on: October 15, 2008, 02:03:16 PM »
Do you need to put your answer in K?

Offline Mitch

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Re: Pressure/Volume- gases
« Reply #2 on: October 15, 2008, 04:03:44 PM »
You need to do the problem in Kelvin.
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Offline nikita

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Re: Pressure/Volume- gases
« Reply #3 on: October 16, 2008, 12:13:35 AM »
sorry, i didnt say it originally, but i tried it in kelvin first and got the wrong number that way, so i tried it in celsius next and it was also wrong.  i got 520K and i subtracted 273 and got 247C.  im doing a practice test from my prof's class last year and the answer says 310C.  ???

Offline Borek

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Re: Pressure/Volume- gases
« Reply #4 on: October 16, 2008, 04:01:36 AM »
I got 247 °C as well.
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Offline JGK

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Re: Pressure/Volume- gases
« Reply #5 on: October 16, 2008, 08:56:13 AM »
247 from me also
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