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admin
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 Posted: Sun Jul 01, 2007 10:30 pm Post subject: |
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| You could have a point if there were "many esters" but I don't see any esters amoung the molecules presented. Recall: an ester has the general formula O=COR This formulation is nowhere in Figure 1 or question 48. |
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admin
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| Posted: Sat Jul 14, 2007 10:51 pm Post subject: |
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If you tell me exactly what part of the problem you don't understand, I could be more helpful.
If you have The Gold Standard text, the reverse reaction is represented in ORG 7.2.3; tracing oxygen in a reaction is shown for esters in ORG 9.4.
You may also want to review your organic mechanisms: www.goldstandard-mcat.com/organic-chemistry-mechanisms |
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admin
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| Posted: Wed Jul 25, 2007 7:33 pm Post subject: |
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Well, the question is just asking: which of the following products was made with water? Answer choice A is a reactant in the passage with water so that can't be the answer. Answer choice D is at the bottom of Figure 1, unrelated to water in the reaction provided.
We are left with answer choices B and C which are both products involving water in the 3rd line of the mechanism provided. Be carefully examining the reactant, you will notice that answer choice B got the H's from water and answer choice C got the O from H2O. Since the O is radiolabelled, it will show up in answer choice C. |
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mcat_premed3832
Joined: 19 Oct 2006
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| Posted: Mon Mar 01, 2010 7:46 pm Post subject: |
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| You are correct that the question should make direct reference to the passage or the ninhydrin reaction. This has been changed. |
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