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Topic: % Yield of Aspirin  (Read 8094 times)

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Offline Confused

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% Yield of Aspirin
« on: August 21, 2006, 09:07:58 AM »
OK so I used 5.0g of salicylic acid and 7.6g of ethanoic anhydride. The acid is the YLR (??)
Yield of aspirin at the end was 3.43g, so am I right in assuming that the final % yield of the product is 68.6%?
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Offline Will

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Re: % Yield of Aspirin
« Reply #1 on: August 21, 2006, 10:06:56 AM »
You are right that the salicylic acid is the limiting reagent meaning that the max. number of moles of aspirin you can get is 0.0362002115. The % yield I worked out is 52.59335288%. How did you get 68.6%?
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Offline Borek

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Re: % Yield of Aspirin
« Reply #2 on: August 21, 2006, 10:36:19 AM »
Quote from: Will on August 21, 2006, 10:06:56 AM
0.0362002115 52.59335288%

Please  >:( don't abuse SD...
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Offline Will

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Re: % Yield of Aspirin
« Reply #3 on: August 21, 2006, 11:21:03 AM »
Quote from: Borek on August 21, 2006, 10:36:19 AM
Quote from: Will on August 21, 2006, 10:06:56 AM
0.0362002115 52.59335288%

Please  >:( don't abuse SD...

OK.
Is 0.036200211496115644906043799070291688272159561265020734757140745119089283767231481673208527553501378576454195075989311959956194848 and 52.593352879942441449261429254481996911367847075074676358042871617499850963673880320888254283392823898121986871259590640230083224% better? LOL
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Offline Borek

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Re: % Yield of Aspirin
« Reply #4 on: August 21, 2006, 11:43:56 AM »
SD = significant digits

Interestingly this meaning is not present on the list...
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Offline Will

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Re: % Yield of Aspirin
« Reply #5 on: August 21, 2006, 11:52:58 AM »
Quote from: Borek on August 21, 2006, 11:43:56 AM
SD = significant digits

Interestingly this meaning is not present on the list...

Yeah, I knew that. Most people (I think) call it significant figures (SF/sf). My math teacher wasn't keen on long significant figures either, but they were quite important for some topics like solving equations by iterative methods.
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Offline Borek

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Re: % Yield of Aspirin
« Reply #6 on: August 21, 2006, 12:32:42 PM »
Quote from: Will on August 21, 2006, 11:52:58 AM
Most people (I think) call it significant figures (SF/sf).

You are probably right, English is my second language and I often fall into language traps  ::)

Back to aspirin yield please ;)
« Last Edit: August 21, 2006, 12:54:13 PM by Borek »
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Offline Confused

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Re: % Yield of Aspirin
« Reply #7 on: August 22, 2006, 05:38:23 AM »
I dont knwo :S I was told that the maximum amount of aspirin at the end result would be 5.0g?
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Offline Borek

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Re: % Yield of Aspirin
« Reply #8 on: August 22, 2006, 05:40:23 AM »
Start with the balanced reaction equation, this is simple stoichiometric problem.
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