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12.8: Ionization Constants of Weak Acids

  • Page ID
  • Acid Formula <emKa at 25 °C Lewis Structure
    acetic CH3CO2H 1.8\times{10}^{-5}
    arsenic H3AsO4 5.5\times{10}^{-3}
    H2AsO4 1.7\times{10}^{-7}
    HAsO42− 5.1\times{10}^{-12}
    arsenous H3AsO3 5.1\times{10}^{-10}
    boric H3BO3 5.4\times{10}^{-10}
    carbonic H2CO3 4.3\times{10}^{-7}
    HCO3 5.6\times{10}^{-11}
    cyanic HCNO 2\times{10}^{-4}
    formic HCO2H 1.8\times{10}^{-4}
    hydrazoic HN3 2.5\times{10}^{-5}
    hydrocyanic HCN 4.9\times{10}^{-10}
    hydrofluoric HF 3.5\times{10}^{-4}
    hydrogen peroxide H2O2 2.4\times{10}^{-12}
    hydrogen selenide H2Se 1.29\times{10}^{-4}
    HSe 1\times{10}^{-12}
    hydrogen sulfate ion HSO4 1.2\times{10}^{-2}
    hydrogen sulfide H2S 8.9\times{10}^{-8}
    HS 1.0\times{10}^{-19}
    hydrogen telluride H2Te 2.3\times{10}^{-3}
    HTe 1.6\times{10}^{-11}
    hypobromous HBrO 2.8\times{10}^{-9}
    hypochlorous HClO 2.9\times{10}^{-8}
    nitrous HNO2 4.6\times{10}^{-4}
    oxyalic H2C2O4 6.0\times{10}^{-2}
    HC2O4 6.1\times{10}^{-5}
    phosphoric H3PO4 7.5\times{10}^{-3}
    H2PO4 6.2\times{10}^{-8}
    HPO42− 4.2\times{10}^{-13}
    phosphorous H3PO3 5\times{10}^{-2}
    H2PO3 2.0\times{10}^{-7}
    sulfurous H2SO3 1.6\times{10}^{-2}
    HSO3 6.4\times{10}^{-8}
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