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Topic: help finding new volumes of gases  (Read 3653 times)

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Offline diesel

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help finding new volumes of gases
« on: March 17, 2008, 05:21:16 PM »
I'm absolutely terrible at these, ive never been able to understand them. Any help would be appreciated!

A sample of gas has a volume of 1.68 liters at 1atm pressure and 158k. What is its volume at STP?



A sample of gas occupies a colume of 0.683 liters at 25deg C. What folume would the gas occupy at 100deg C?


thanks ahead of time!

Offline Borek

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Re: help finding new volumes of gases
« Reply #1 on: March 17, 2008, 05:47:41 PM »
Please read forum rules. No matter how terrible you are, for sure you know something - show what you know, we will help you move ahead.
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Offline Arkcon

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Re: help finding new volumes of gases
« Reply #2 on: March 17, 2008, 06:18:48 PM »
What info does the first sentence give you, that you can use in the formula PV=nRT, , to find more info, that you need to solve the second sentence..
Hey, I'm not judging.  I just like to shoot straight.  I'm a man of science.

Offline diesel

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Re: help finding new volumes of gases
« Reply #3 on: March 17, 2008, 06:42:23 PM »
so to start off it would be (1.68)(1)=n(.0821)(158k) ?

Offline Arkcon

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Re: help finding new volumes of gases
« Reply #4 on: March 18, 2008, 02:02:00 PM »
so to start off it would be (1.68)(1)=n(.0821)(158k) ?

Great, now you have n, what do you get from the second sentence, that's different for the first, that you use to solve for the unknown in the second sentence?

Tip:  don't neglect units, if they don't match your constant, or what you've given later, you'll have to convert, or you'll never get the answer right.  And we don't want to lose any more mars probes, we expect better from scientists. 8)

Reference obscure?
Hey, I'm not judging.  I just like to shoot straight.  I'm a man of science.

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