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Polyprotic Acid

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    282817
  • CHEM 2300, In-class Exercises, Class 20

    Name: _________________________

     

    Phosphoric acid, H3PO4 is a triprotic acid.               pKa1= 2.16           pKa2=7.21            pKa3=12.32

    1. Estimate the pH in a 0.450 M phosphoric acid solution.

     

     

     

     

     

     

     

     

     

     

     
    1. Estimate the pH in a 0.450 M HPO42- solution

     

     

     

     

     

     

     

     

     

     

    1. Find the concentrations of the following species in the 0.450 M phosphoric acid solution from Problem 1: H3PO4, H2PO4-

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

    CHEM 2300, In-class Exercises, Class 22

    Name: _________________________

    Citric acid, C6H8O7, is a triprotic acid.         pKa1= 3.128        pKa2=4.761         pKa3=6.396

    1. Given 25 mL of a 0.1 M solution of citric acid, calculate the pH after the addition of the following amounts of a 0.1 M solution of NaOH.
      1. 0.00 mL    e. 25.0 mL                            i. 62.5 mL
      2. 10.0 mL    f. 37.5 mL                             j. 70.0 mL
      3. 12.5 mL    g. 40.0 mL                            k. 75.0 mL
      4. 100.0 mL    h. 50.0 mL

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

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