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Positive and negative in destroyer answer choice

Discussion in 'DAT Discussions' started by vvvv, Jun 5, 2008.

  1. vvvv

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    in ochem I saw couple questions that have +- in front of the products. what do they mean by that? anybody knows?
     
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  3. Mstoothlady2012

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    for example........?
     
  4. creative8401

    creative8401 Im Anush Hayastan

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    Hi. I’ve seen that one too. For example, in question 29, we see a +- sign, and from my understanding, this is used to show enantiomers of the product. For example, when we are dealing with BH3, THF, with H2O2 and OH-, the product is syn addition of OH and H. Thus, it can add cis and trans to the product. In a much deeper understanding, it refers to the plane of polarized light. Such things are determined experimentally, but it means that one bends light clockwise and the other counterclockwise.
    :)
     
  5. DDSguyLA

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    well said
     
  6. TheWiredNerv

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    To put it simply, + and - refers to the way light is polarized by the product.
     
  7. creative8401

    creative8401 Im Anush Hayastan

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    Hi everyone. You have to excuse sometimes my lengthy explanations to some of the questions, but since I don't know how much of an understanding a person has for the concepts, I structure my answers to build from the basics and develop a deeper understanding for the concepts. :)
     
  8. smile101

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    You better know which rxns give enatiomers and and which ones give meso or optically active compounds when reacted. They certainly show up on the test.
     

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