Finding g of gas from a given L at STP (stochiometry)

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Joined: Fri Jan 10, 2020 2:51 pm

Finding g of gas from a given L at STP (stochiometry)

Post by sen117 » Wed Jan 15, 2020 2:02 pm


Could you please explain the following questions on the stochiometry quizzes (CR)?

Quiz 4,
Given this balanced equation for the combustion of propane, what is the approximate mass of carbon dioxide produced by the combustion of 2.24L of propane at STP?
Could you please explain how to find the gram or mole of the propane from the given volume (2.24L)?

Also, when quiz 1 of stochiometry changes the condition to high-volume & high pressure, how does it affect the calculation? I am still puzzled after reading the answer keys.

Thank you so much for your help in advance!
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Joined: Sat Mar 30, 2019 8:39 pm

Re: Finding g of gas from a given L at STP (stochiometry)

Post by NS_Tutor_Mathias » Thu Jan 16, 2020 12:17 am

The hangup you're having might be converting liters of propane to moles of propane. Luckily enough, there is an easy rule of thumb for any ideal-ish gas: One mole of a given gas occupies about 22.4L at STP.

Therefore, we know that 2.24 L of propane is just 0.1 moles of propane. I think you can take it from there, but do let me know if anything about this problem is still unclear and I'll happily walk you through it.
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