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Homework Help: Chemistry Indicators Problem

  1. Feb 15, 2007 #1
    1. The problem statement, all variables and given/known data
    Select a suitable indicator for each of the following titrations:
    HNO3 added to NaCN

    LiOH added to HNO2
    2. Relevant equations
    all i know is Ka(HIn)=[H3O] at transition point and pKa(HIn)=pH at transition point



    3. The attempt at a solution
    the book I have is really skimpy on this, and is has no other information, or even an example.

    For LiOH + HNO2 <----> H20 + LiNO2
    ic that Li doesn't hydrolyze and NO2 does. the ka for NO2 is 5.1E-4 which should also be the Ka then I -log(5.1E-4) and I get the wrong answer????? The answer should be an indicator with a pH range around 8-10. I don't get it, can someone please help me?
     
  2. jcsd
  3. Feb 18, 2007 #2

    Borek

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    Staff: Mentor

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