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16.10: Solubility Products

  • Page ID
    220807
  • The following table provides pKsp and Ksp values for selected compounds, organized by the anion. All values are from Martell, A. E.; Smith, R. M. Critical Stability Constants, Vol. 4. Plenum Press: New York, 1976. Unless otherwise stated, values are for 25 oC and zero ionic strength.

    Bromide (\(\ce{Br-}\)) pKsp Ksp
    \(\ce{CuBr}\) 8.3 \(5. \times10^{-9}\)
    \(\ce{AgBr}\) 12.3 \(5.0 \times 10^{-13}\)
    \(\ce{Hg2Br2}\) 22.25 \(5.6 \times 10^{-23}\)
    \(\ce{HgBr2} \: (\mu = 0.5 \text{ M})\) 18.9 \(1.3 \times 10^{-19}\)
    \(\ce{PbBr2} \: (\mu = 0.5 \text{ M})\) 5.68 \(2.1 \times 10^{-6}\)

     

    Carbonate (\(\ce{CO3^{2-}}\)) pKsp Ksp
    \(\ce{MgCO3}\) 7.46 \(3.5 \times 10^{-8}\)
    \(\ce{CaCO3}\) (calcite) 8.35 \(4.5 \times 10^{-9}\)
    \(\ce{CaCO3}\) (aragonite) 8.22 \(6.0 \times 10^{-9}\)
    \(\ce{SrCO3}\) 9.03 \(9.3 \times 10^{-10}\)
    \(\ce{BaCO3}\) 8.3 \(5.0 \times 10^{-9}\)
    \(\ce{MnCO3}\) 9.3 \(5.0 \times 10^{-10}\)
    \(\ce{FeCO3}\) 10.68 \(2.1 \times 10^{-11}\)
    \(\ce{CoCO3}\) 9.98 \(1.0 \times 10^{-10}\)
    \(\ce{NiCO3}\) 6.87 \(1.3 \times 10^{-7}\)
    \(\ce{Ag2CO3}\) 11.09 \(8.1 \times 10^{-12}\)
    \(\ce{Hg2CO3}\) 16.05 \(8.9 \times 10^{-17}\)
    \(\ce{ZnCO3}\) 10 \(1.0 \times 10^{-10}\)
    \(\ce{CdCO3}\) 13.74 \(1.8 \times 10^{-14}\)
    \(\ce{PbCO3}\) 13.13 \(7.4 \times 10^{-14}\)

     

    Chloride (\(\ce{Cl-}\)) pKsp Ksp
    \(\ce{CuCl}\) 6.73 \(1.9 \times 10^{-7}\)
    \(\ce{AgCl}\) 9.74 \(1.8\times 10^{-10}\)
    \(\ce{Hg2Cl2}\) 17.91 \(1.2 \times 10^{-18}\)
    \(\ce{PbCl2}\) 4.78 \(2.0 \times 10^{-19}\)

     

    Chromate (\(\ce{CrO4^{2-}}\)) pKsp Ksp
    \(\ce{BaCrO4}\) 9.67 \(2.1 \times 10^{-10}\)
    \(\ce{CuCrO4}\) 5.44 \(3.6 \times 10^{-6}\)
    \(\ce{Ag2CrO4}\) 11.92 \(1.2 \times 10^{-12}\)
    \(\ce{Hg2CrO4}\) 8.7 \(2.0 \times 10^{-9}\)

     

    Cyanide (\(\ce{CN-}\)) pKsp Ksp
    \(\ce{AgCN}\) 15.66 \(2.2 \times 10^{-16}\)
    \(\ce{Zn(CN)2} \: (\mu = 3.0 \text{ M})\) 15.5 \(3. \times 10^{-16}\)
    \(\ce{Hg2(CN)2}\) 39.3 \(5. \times 10^{-40}\)

     

    Ferrocyanide (\(\ce{Fe(CN)6^{4-}}\)) pKsp Ksp
    \(\ce{Zn2[Fe(CN)6]}\) 15.68 \(2.1 \times 10^{-16}\)
    \(\ce{Cd2[Fe(CN)6]}\) 17.38 \(4.2 \times 10^{-18}\)
    \(\ce{Pb2[Fe(CN)6]}\) 18.02 \(9.5 \times 10^{-19}\)

     

    Fluoride (\(\ce{F-}\)) pKsp Ksp
    \(\ce{MgF2}\) 8.18 \(6.6 \times 10^{-9}\)
    \(\ce{CaF2}\) 10.41 \(3.9 \times 10^{-11}\)
    \(\ce{SrF2}\) 8.54 \(2.9 \times 10^{-9}\)
    \(\ce{BaF2}\) 5.76 \(1.7 \times 10^{-6}\)
    \(\ce{PbF2}\) 7.44 \(3.6 \times 10^{-8}\)

     

    Hydroxide (\(\ce{OH-}\)) pKsp Ksp
    \(\ce{Mg(OH)2}\) 11.15 \(7.1 \times 10^{-12}\)
    \(\ce{Ca(OH)2}\) 5.19 \(6.5 \times 10^{-6}\)
    \(\ce{Ba(OH)2 * 8 H2O}\) 3.6 \(3. \times 10^{-4}\)
    \(\ce{La(OH)3}\) 20.7 \(2. \times 10^{-21}\)
    \(\ce{Mn(OH)2}\) 12.8 \(1.6 \times 10^{-13}\)
    \(\ce{Fe(OH)2}\) 15.1 \(8. \times 10^{-16}\)
    \(\ce{Co(OH)2}\) 14.9 \(1.3 \times 10^{-15}\)
    \(\ce{Ni(OH)2}\) 15.2 \(6. \times 10^{-16}\)
    \(\ce{Cu(OH)2}\) 19.32 \(4.8 \times 10^{-20}\)
    \(\ce{Fe(OH)3}\) 38.8 \(1.6 \times 10^{-39}\)
    \(\ce{Co(OH)3} \: (T = 19 \text{°C})\) 44.5 \(3. \times 10^{-45}\)
    \(\ce{Ag2O} \: ( + \: \ce{H2O} \ce{<=>} \ce{2 Ag+} + \ce{2 OH-})\) 15.42 \(3.8 \times 10^{-16}\)
    \(\ce{Cu2O} \: ( + \: \ce{H2O} \ce{<=>} \ce{2 Cu+} + \ce{2 OH-})\) 29.4 \(4.u \times 10^{-30}\)
    \(\ce{Zn(OH)2}\) (amorphous) 15.52 \(3.0 \times 10^{-16}\)
    \(\ce{Cd(OH)2 (\beta)}\) 14.35 \(4.5 \times 10^{-15}\)
    \(\ce{HgO} \text{ (red)} \: ( + \: \ce{H2O} \ce{<=>} \ce{Hg^{2+}} + \ce{2 OH-})\) 25.44 \(3.6 \times 10^{-26}\)
    \(\ce{SnO} \: ( + \: \ce{H2O} \ce{<=>} \ce{Hg^{2+}} + \ce{2 OH-})\) 26.2 \(6. \times 10^{-27}\)
    \(\ce{PbO} \text{ (yellow)} \: ( + \: \ce{H2O} \ce{<=>} + \ce{Pb^{2+}} + \ce{2 OH-}\) 15.1 \(8. \times 10^{-16}\)
    \(\ce{Al(OH)3 \: (\alpha)}\) 33.5 \(3. \times 10^{-34}\)

     

    Iodate (\(\ce{IO3-}\)) pKsp Ksp
    \(\ce{Ca(IO3)2}\) 6.15 \(7.1 \times 10^{-7}\)
    \(\ce{Ba(IO3)2}\) 8.81 \(1.5 \times 10^{-9}\)
    \(\ce{AgIO3}\) 7.51 \(3.1 \times 10^{-8}\)
    \(\ce{Hg2(IO3)2}\) 17.89 \(1.3 \times 10^{-18}\)
    \(\ce{Zn(IO3)2}\) 5.41 \(3.9 \times 10^{-6}\)
    \(\ce{Cd(IO3)2}\) 7.64 \(2.3 \times 10^{-8}\)
    \(\ce{Pb(IO3)2}\) 12.61 \(2.5 \times 10^{-13}\)

     

    Iodide (\(\ce{I-}\)) pKsp Ksp
    \(\ce{AgI}\) 16.08 \(8.3 \times 10^{-17}\)
    \(\ce{Hg2I2}\) 28.33 \(4.7 \times 10^{-29}\)
    \(\ce{HgI2} \: (\mu = 0.5 \text{ M})\) 27.95 \(1.1 \times 10^{-28}\)
    \(\ce{PbI2}\) 8.1 \(7.9 \times 10^{-9}\)

     

    Oxalate (\(\ce{C2O4^{2-}}\)) pKsp Ksp
    \(\ce{CaC2O4} \: (\mu = 0.1 \text{ M, } T = 20 \text{°C})\) 7.9 \(1.3 \times 10^{-8}\)
    \(\ce{BaC2O4} \: (\mu = 0.1 \text{ M, } T = 20 \text{°C})\) 6 \(1. \times 10^{-6}\)
    \(\ce{SrC2O4} \: (\mu = 0.1 \text{ M, } T = 20 \text{°C})\) 6.4 \(4. \times 10^{-7}\)

     

    Phosphate (\(\ce{PO4^{3-}}\)) pKsp Ksp
    \(\ce{Fe3(PO4)2 * 8 H2O}\) 36 \(1. \times 10^{-36}\)
    \(\ce{Zn3(PO4)2 * 4 H2O}\) 35.3 \(5. \times 10^{-36}\)
    \(\ce{Ag3PO4}\) 17.55 \(2.8 \times 10^{-18}\)
    \(\ce{Pb3(PO4)2} \: (T = 38 \text{ °C})\) 43.55 \(3.0 \times 10^{-44}\)

     

    Sulfate (\(\ce{SO4^{2-}}\)) pKsp Ksp
    \(\ce{CaSO4}\) 4.62 \(2.4 \times 10^{-5}\)
    \(\ce{SrSO4}\) 6.5 \(3.2 \times 10^{-7}\)
    \(\ce{BaSO4}\) 9.96 \(1.1 \times 10^{-10}\)
    \(\ce{Ag2SO4}\) 4.83 \(1.5 \times 10^{-5}\)
    \(\ce{Hg2SO4}\) 6.13 \(7.4 \times 10^{-7}\)
    \(\ce{PbSO4}\) 7.79 \(1.6 \times 10^{-8}\)

     

    Sulfide (\(\ce{S^{2-}}\)) pKsp Ksp
    \(\ce{MnS} \: (\text{green})\) 13.5 \(3. \times 10^{-14}\)
    \(\ce{FeS}\) 18.1 \(8. \times 10^{-19}\)
    \(\ce{CoS} \: (\beta)\) 25.6 \(3. \times 10^{-26}\)
    \(\ce{NiS} \: (\gamma)\) 26.6 \(3. \times 10^{-27}\)
    \(\ce{CuS}\) 36.1 \(8. \times 10^{-37}\)
    \(\ce{Cu2S}\) 48.5 \(3. \times 10^{-49}\)
    \(\ce{Ag2S}\) 50.1 \(8. \times 10^{-51}\)
    \(\ce{ZnS} \: (\alpha)\) 24.7 \(2. \times 10^{-25}\)
    \(\ce{CdS}\) 27 \(1. \times 10^{-27}\)
    \(\ce{Hg2S} \: (\text{red})\) 53.3 \(5. \times 10^{-54}\)
    \(\ce{PbS}\) 27.5 \(3. \times 10^{-28}\)

     

    Thiocyanate (\(\ce{SCN-}\)) pKsp Ksp
    \(\ce{CuSCN} \: (\mu = 5.0 \text{ M})\) 13.4 \(4.0\times 10^{-14}\)
    \(\ce{AgSCN}\) 11.97 \(1.1\times 10^{-12}\)
    \(\ce{Hg2(SCN)2}\) 19.52 \(3.0\times 10^{-20}\)
    \(\ce{Hg2(SCN)2} \: (\mu = 1.0 \text{ M})\) 19.56 \(2.8\times 10^{-20}\)

     

     

     

     

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