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Homework Help: Question about Compound Purity

  1. Oct 7, 2008 #1
    1. The problem statement, all variables and given/known data
    I recrystallized an unknown carboxylic acid, then found the melting point of the dried compound and identified it. The melting point range was narrow and that said to me that the compound was pure, but the percent recovery was very low (< 40 %). Indicating there was still a significant amount of impurities. I just wanted to know how to resolve these conflicting results and/or which contribution is the most important in determining purity. Forgive me if this question is stupid.

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Oct 7, 2008 #2


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    By the " recovery " do you mean ( experimental yield / theoretical yield ) x 100 %?
  4. Oct 8, 2008 #3
    No, the percent recovery. (mass of pure compound)/(mass of impure compound) x 100 %. I'd only heard of percent yield before this class, but this formula is what was given. Only to be used in purification processes.
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