How to use the combined gas law formula in calculations

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CheesyPeeps
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I am studying National 5 physics, and my exam is tomorrow. I need some last-minute help.
I'm struggling a little bit with the combined gas law, P1V1/T1 = P2V2/T2, and I'm not sure why.
It would help me a lot if you could show step-by-step how the formula is used.
Thanks for your time, it's very much appreciated.
 
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CheesyPeeps said:
I'm struggling a little bit with the combined gas law, P1V1/T1 = P2V2/T2, and I'm not sure why.

Where exactly are you having problems with it?
 
Drakkith said:
Where exactly are you having problems with it?

That's the problem: I'm not sure where things are going wrong. I think it may be when I substitute in the values and then have to rearrange the equation, which seems strange because usually rearranging equations is the easiest part!
 
I'd suggest finding a homework question and posting it in the homework forums, that way the homework helpers can walk you through it and find out where you're having trouble.
 
I'm sure I'll stop by your thread later, as we are studying the gas laws in class this week. :wink:
 
Update: I did some exam-style questions on it and I've got it now! I think it was a mixture of me overcomplicating it and occasionally forgetting to convert the temperature into kelvin :smile:
 
CheesyPeeps said:
and occasionally forgetting to convert the temperature into kelvin

Yes, I just clarified this with my instructor tonight. Makes sense, otherwise you end up with negative numbers when your temperature goes below zero!