Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

NaHCO3 and aspirin.

  1. Oct 25, 2004 #1
    Hi ppl,
    I was wondering could someone help me with this explanation. Why does the addition of Sodium Hydrogencarbonate help an aspirin to dissolve. In tablets of aspirin, acetylsalicylcic acid is mixed with sodium hydrogencarbonate and when the soluble aspirin tablet is dissolved in water the acetylsalicylcic acid and the sodium hydrogencarbonate react together.

    Thanks a lot,
    joe
     
  2. jcsd
  3. Oct 25, 2004 #2

    movies

    User Avatar
    Science Advisor

    In aqueous solution the basic NaHCO3 can deprotonate the acidic acetylsalicylic acid. The resulting charged species (carboxylate anion) is very soluble in water.

    Without the base then the acid would be protonated and therefore uncharged. The rest of the molecule is rather non-polar and thus not very soluble in polar solvents like water.
     
  4. Oct 26, 2004 #3

    chem_tr

    User Avatar
    Science Advisor
    Gold Member

    As Movies explained the issue well, I will only give the reaction scheme.

    [tex]HSal + NaHCO_3 \longrightarrow Sal^- Na^+ + CO_2 + H_2O[/tex]

    Normally, H2CO3 is expected to be formed, but is very unstable to yield carbon dioxide and water for lower energy and higher unregularity (entropy) needs.
     
  5. Jun 30, 2011 #4
    It's very similar to that between benzoic acid and sodium hydrogencarbonate.

    C6H5COOH + NaHCO3 -----> C6H5COONa + CO2 + H2O
    NaHCO3
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Similar Discussions: NaHCO3 and aspirin.
  1. ASA and ASPIRIN (Replies: 5)

  2. Aspirin questions (Replies: 1)

Loading...