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Topic: Combustion/Gas Law problem  (Read 7475 times)

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Offline chanelo

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Combustion/Gas Law problem
« on: October 10, 2012, 08:24:45 PM »
The problem is:
2C8H18 + 25O2  :rarrow: 16CO2 + 18H2O
If 394 mol octane combusts, what volume of carbon dioxide is produced at 28.0°C and 0.995 atm?

I started by finding out how many moles of carbon dioxide are produced from the combustion of octane by doing 394 mol x (16 mol CO2 / 2 mol C8H18) and got 3152 mol CO2.
Then I did
V = nRT / P
V = (3152)(0.082)(28 + 273) / 0.0995 and I got 7.82 x 10-4 L. But this is wrong. Can someone tell me where I went wrong?

Offline EpicWinston

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Re: Combustion/Gas Law problem
« Reply #1 on: October 10, 2012, 11:05:27 PM »
Well that's odd.

What is the answer suppose to be? I did the problem and I got the same answer. The only flaw I saw was that you divided by 0.0995 instead of 0.995, but we still arrived at the same answer so you probably typed it correctly in your calculator.

Offline Borek

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Re: Combustion/Gas Law problem
« Reply #2 on: October 11, 2012, 04:37:26 AM »
I got 7.82 x 10-4 L.

10-4? Below 1 mL of gas?
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Offline mamid

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Re: Combustion/Gas Law problem
« Reply #3 on: October 11, 2012, 08:59:37 AM »
I did it too, and got 7.82 x 104. That's 4, as opposed to -4. It seems you people just read the result wrong.

Offline EpicWinston

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Re: Combustion/Gas Law problem
« Reply #4 on: October 11, 2012, 02:13:47 PM »
Yea that's what I meant 104 my bad

Offline Borek

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Re: Combustion/Gas Law problem
« Reply #5 on: October 11, 2012, 02:49:58 PM »
To be precise, I got 7.83×104
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Offline EpicWinston

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Re: Combustion/Gas Law problem
« Reply #6 on: October 12, 2012, 09:44:29 AM »
How did you get that program @Borek?

Offline Borek

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Re: Combustion/Gas Law problem
« Reply #7 on: October 12, 2012, 12:42:50 PM »
I wrote it. But you can just buy, see my signature ;)
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