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# Finding Equilibrium moles watch

1. To get the equilibrium moles of ethanol, why did they subtract the equilibrium moles of the products (0.294) from the (start) moles of ethanol?? :/

Why didn't they subtract the equilibrium moles of ethanoic acid (0.106) instead?
2. That's the amount which is used up in the reaction. You can find it by subtracting the moles at the start with the moles at the end for any reactant/product you know. In this case, 0.4 - 0.106 = 0.294. If this is used up with the first reactant, you can use the numbers in front of each product/reactant (stoichiometry) to tell you what factor to multiply this by for how many moles of the other reactant is used up. In this case, as they are all 1:1, 0.294 moles is used up for each of them. If it was 1:2 say, 0.294 moles: 0.588 moles would be the moles used up.

They wouldn't subtract the moles of ethanolic acid, as this is the amount of moles left over, not the amount used up in the reaction.

Hope this helps.
That's the amount which is used up in the reaction. You can find it by subtracting the moles at the start with the moles at the end for any reactant/product you know. In this case, 0.4 - 0.106 = 0.294. If this is used up with the first reactant, you can use the numbers in front of each product/reactant (stoichiometry) to tell you what factor to multiply this by for how many moles of the other reactant is used up. In this case, as they are all 1:1, 0.294 moles is used up for each of them. If it was 1:2 say, 0.294 moles: 0.588 moles would be the moles used up.

They wouldn't subtract the moles of ethanolic acid, as this is the amount of moles left over, not the amount used up in the reaction.

Hope this helps.
Thank you!!

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Updated: June 13, 2016
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