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Acid and Bases

  1. Oct 8, 2004 #1
    I feel like an idiot asking this in a chemistry forum, but I have looked everywhere. I don't understand what acid and bases are, and how they work. I understand chemical bonding down to quantum physics, but I just don't understand this, what is happening in an acid?
  2. jcsd
  3. Oct 8, 2004 #2


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    Well, there are two theories that explain Acid and Bases. One is Bronsted-Lowry Theory which deals with the Hydrogen Proton exchange, and the other is Lewis Theory whish deals with a pair of electrons exchange. The first theory limits acids and bases greatly, while the second allows substances in the first theories that are not considered acid to be an acid.

    Look up Bronsted-Lowry Theory of Acid and Bases, and Lewis Theory.
    By the way, there was this other theory i believe it was from Arrhenius (Spelling?), which consisted in simply putting a substance in water, and if it showed H+ ions it was an acid, and if it showed OH- ions it was a base.
  4. Oct 8, 2004 #3
    Helpful site

    This is a really helpful site for acids and bases

    http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch11/acidbaseframe.html [Broken]
    Last edited by a moderator: May 1, 2017
  5. Oct 9, 2004 #4


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    Dear Dual Op Amp,

    If you understand quantum physics, maybe molecular orbital theory may be of great help. Acids are generally electron-deficient or wants to send electrons outside; in molecular orbital theory, we explain these with electron absence in antibonding orbitals or in LUMO (lowest unoccupied molecular orbital) energy level.

    A base, in turn, can be explained with electron-pair presence in HOMO (highest occupied molecular orbital); if it is a non-bonding molecular orbital, the basicity is too strong to be stable enough.

    Hope this approach helps you along with those posted by the other friends.
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