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Acid/Base Chemistry

  1. Feb 22, 2007 #1
    1. The problem statement, all variables and given/known data
    Which of the substanced KCN, NaF, KBr, LiCl, and NH4Br will react with water to produce non-neutral solutions?
    a.) KCN, LiCl and NH4Br
    b.) KCN, NaF and NH4Br
    c.) NaF, LiCl and NH4Br
    d.) NaF, KBr and NH4Br
    e.) KCN, KBr and LiCl

    2. Relevant equations

    3. The attempt at a solution
    Okay, so I ruled out e because NH4+ is a weak acid and should produce a non-neutral solution in water. The rest all appear to be conjugate bases of acids, but I'm having trouble deciding which ones will result in a non-neutral pH.

    So... I guess I've been given the conjugate bases of two weak acids (HCN and HF) and the conjugate bases of two strong acids (HBr and HCl) I'm thinking... since HBr and HCl are strong acids, the Cl- and Br- in LiCl and KBr added to water aren't going to do much. Whereas maybe the F- in NaF and CN- in KCN would set up an equilibrium in water? So I guess I'm thinking b, but I'm really not sure. Any help is appreciated.
  2. jcsd
  3. Feb 23, 2007 #2


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    I agree with your logic...
  4. Mar 1, 2007 #3
    Forgot I posted this! Thanks for your response. :)
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