J.R. S. answered • 02/23/19
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CH3CH2OH + 3O2 ==> 2CO2 + 3H2O ... balanced equation for combustion of ethanol
moles ethanol = 2.10 g x 1 mole/ 46 g = 0.0457 moles ethanol
moles O2 = 10.93 g x 1 mole/32 g = 0.342 moles O2
Since mole ratio of O2 : ethanol is 3 : 1, ethanol is limiting
Look up the molar enthalpy of the reaction and multiply by 0.0457 to get the enthalpy for THIS reaction
J.R. S.
tutor
You can’t find it without more information. You have to look up the molar enthalpy of combustion of ethanol and use that value to calculate the answer.
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02/24/19
Shari B.
So I got my reactant enthalpy to be -1013 and i multiplied it by 0.0457 and I got -46.2941 but it still is not saying that that answer is right. Is there something that I missed?
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02/24/19
J.R. S.
tutor
-1368kJ/mole is the value I found. Whoever gave you this question is being unfair to you without giving you a value for the standard enthalpy of combustion. Try using the value I found and see if that gives you the correct answer.
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02/25/19
Shari B.
it's still saying it's wrong. I tried asking a couple people in the class and they said they couldn't figure it out either so I have no clue what to do at this point.
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02/25/19
Shari B.
How do I find the enthalpy? I have tried it multiple times but it has not been the right answer02/24/19