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Lets think about the acidity

  1. Mar 22, 2016 #1
    Well.......hello brothers and sisters........may I know whether benzoic acid is more acidic or formic acid.......because I have two arguments which support don't support each other....:frown::frown:
  2. jcsd
  3. Mar 22, 2016 #2


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    Staff: Mentor

    Tell us what information you found.
  4. Mar 22, 2016 #3
    argument 1: Due to the presence of the aromatic ring which pulls electrons slightly due to the presence sp2 hybridized carbon atom, decreases the electron density on the carboxylate carbon atom making it more acidic than formic acid which doesn't have such interaction.Thus, benzoic acid is more stronger than formic acid.

    argument 2: Due to the presence of two oxygen atoms in carboxylate ion which pulls the electron from the aromatic ring slightly towards it as the oxygen atoms are more electronegative compared to sp2 hybridized carbon atoms. Thus increasing the electron density on the carboxylate carbon making benzoic acid less acidic compared to formic as there no such interaction in formic acid (negligible).

    I have these two fighting arguments.......:oldfrown::oldconfused:
  5. Mar 22, 2016 #4


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    Staff: Mentor

    Such arguments are quite handwavy, you are comparing apples and oranges.

    Just check Ka values.
  6. Mar 22, 2016 #5
    yes the ka values say that formic acid is more acidic but my reasonings are not able to fit..........:oldcry:
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