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12.5: Ionization Constants of Weak Acids

  • Page ID
    207534
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    Ionization Constants of Weak Acids
    Acid Formula Ka at 25 °C Lewis Structure
    acetic CH3CO2H 1.8 × 10−5 alt
    arsenic H3AsO4 5.5 × 10−3 alt
    alt 1.7 × 10−7
    alt 5.1 × 10−12
    arsenous H3AsO3 5.1 × 10−10 alt
    boric H3BO3 5.4 × 10−10 alt
    carbonic H2CO3 4.3 × 10−7 alt
    alt 4.7 × 10−11
    cyanic HCNO 2 × 10−4 alt
    formic HCO2H 1.8 × 10−4
    hydrazoic HN3 2.5 × 10−5
    hydrocyanic HCN 4.9 × 10−10
    hydrofluoric HF 3.5 × 10−4
    hydrogen peroxide H2O2 2.4 × 10−12 alt
    hydrogen selenide H2Se 1.29 × 10−4
    HSe 1 × 10−12
    hydrogen sulfate ion alt 1.2 × 10−2 alt
    hydrogen sulfide H2S 8.9 × 10−8
    HS 1.0 × 10−19
    hydrogen telluride H2Te 2.3 × 10−3
    HTe 1.6 × 10−11
    hypobromous HBrO 2.8 × 10−9
    hypochlorous HClO 2.9 × 10−8
    nitrous HNO2 4.6 × 10−4 alt
    oxalic H2C2O4 6.0 × 10−2 alt
    alt 6.1 × 10−5
    phosphoric H3PO4 7.5 × 10−3 alt
    alt 6.2 × 10−8
    alt 4.2 × 10−13
    phosphorous H3PO3 5 × 10−2 alt
    alt 2.0 × 10−7
    sulfurous H2SO3 1.6 × 10−2 alt
    alt 6.4 × 10−8

    12.5: Ionization Constants of Weak Acids is shared under a CC BY license and was authored, remixed, and/or curated by OpenStax.

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