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What characterizes an acid as strong?

  1. Jun 13, 2005 #1
    I've posted this question in another thread... didn't get the answer though

    Why does a strong acid (or a base) ionizes to a higher extent? Is this extent of ionization the only criteria for characterizing an acid (or a base) as strong or weak. Is it the simple bond polarization phenomenon that causes the ionization?
  2. jcsd
  3. Jun 13, 2005 #2
    i'm not a tutor but i would guess its due to bond strength. probably wrong tho
  4. Jun 13, 2005 #3
    Does hydrogen bonding have some effect on pH?
  5. Jun 14, 2005 #4
    Its due to the 'regularity' of the acid molecule to dissociate into Oxonium ions. For example, Hydrogen fluride has only something like 10% - 20% of its molecules dissociating into oxonium ions, while a 'strong' acid such as hydrochloric acid will have 90 - 100% dissocition of its molecules into oxonium ions.
  6. Jun 15, 2005 #5
    So, my question stands unanswered! Why does HCl dissociate to such a high extent and while HF to only a little extent???
  7. Jun 15, 2005 #6
    Its because the H-F Bond is much stronger than the H-Cl bond.

    Note: you asked why strong acids IONIZE to a higher extent, and technically, this has been answered.
  8. Jun 15, 2005 #7
    It is due primarily to bond strength, and temp...water only has the ability to pull apart some acids, that is one reason why 'sensitive' reactions take place @ lower temps. The acids dissassociate less because the water only has a certain amount of strength to rip them apart in the first place.
  9. Jun 16, 2005 #8
    Hmmm... OK! I admit, Bladibla, you are right. You've answered my question. I actually overlooked the first sentence of your reply. Thanks!

    Can someone please name around ten strong acids, strong bases, weak acids and weak bases and give their respective %ionization?
  10. Jun 16, 2005 #9
    I got it myself, not TEN though!

    http://www.dbhs.wvusd.k12.ca.us/webdocs/AcidBase/Strong-Weak-AcidBase.html [Broken]
    http://www.members.aol.com/profchm/tcjc_ch15.html [Broken]

    I'll be back with more questions in future. Inshallah
    Last edited by a moderator: May 2, 2017
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