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Homework Help: Quick citric acid question

  1. Nov 9, 2011 #1
    1. The problem statement, all variables and given/known data

    just a curosity of mine. citric acid is triprotic, with a pKa3 of 5.41, so does this mean that i will be inf ull conjugate base form(3-) at solution pH >5.41

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Nov 10, 2011 #2


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    Staff: Mentor

    No, at pH 5.41, [HA2-] = [A3-]. It always works this way.

    Check out this page: titrations.info/acid-base-titration-indicators

    While discussion there is about pH indicators, equation 2 describes every weak acid you can think of.
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