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Solubility and Ionic Strength (Fry-Petit)

  • Page ID
    282901
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    Reading: Chapter 12 (sections 1-2)

    Homework: Chapter 12: 2, 4, 5, 9-13.b, 14-19

    Solubility,IonicStrength.png

    • What was the effect of NaI on the solubility of PbI2? Why?

    \[\ce{PbI_{2(s)} ⇆ Pb^2+ + 2I-}\nonumber\]

     

     

     

     

     

    • What is the effect of adding KNO3 to the above rxn? Why?

     

     

     

     

    STOP


    IonicStrength.png

    Activity.png

    NewEquilibrium,pHEquations.png

    Table12-1_ActivityCoefficients.png

    IonicStrength_Quantitative.png

    • What is the ionic strength of a 0.00333 M solution of PbI2 and the activity coefficient of Pb2+ and I-?

       

       

       

       

       

       

       

       

       

    STOP


    • Calculate the solubility of 0.00333 M PbI2 (Ksp 7.9×10-9) solution with 2 different scenarios.
      • Assume PbI2 solubility is low enough not to effect ionic strength.

         

         

         

         

         

         

         

      • Assume PbI2 solubility effects ionic strength.

         

         

         

         

      • How does the solubility differ and how can you explain the difference?

     

     

     

     

    STOP


    EstimatingActivityCoefficients.png

    • Calculate the ionic strength and solubility of a saturated solution of 0.0125 M PbI2 with 0.05 M NaCl. Assume PbI2 solubility effects ionic strength.
      • Calculate the ionic strength

         

         

         

         

        STOP


      • Interpolate to determine the \(γ_{Pb^{2+}}\) and \(γ_{I^-}\)

         

         

         

         

         

         

         

         

         

      • Determine the solubility








     

    ActivityRelations.png

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