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Strong and Weak Electrolytes

  1. Nov 3, 2006 #1
    I am slightly confused about the following statement from my chemistry book: "Note that essentially all solid ionic compounds are strong electrolytes in solution, because, no matter to what extent they dissolve, they give only ions" (https://www.amazon.com/Chemistry-Sc...f=sr_1_1/002-8266887-3708046?ie=UTF8&s=books"). Isn't a strong electrolyte something that dissociates completely or almost completely into ions?
    A solid ionic compound that dissociates only say, 5% into ions is still considered a strong electrolyte?
    That seems to me to be a weak electrolyte ("Weak electrolytes are those electrolytes which in water solutions dissociate only partially, giving ions and which are in equilibrium with undissociated molecules "(http://www.ktf-split.hr/glossary/en_o.php?def=weak electrolyte"))
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Nov 4, 2006 #2
    Well that statement, in my opinion, answers half the question. Basically something is a strong electrolyte yes if it dissociates to a large extent, determined by the equilibrium constant for the disolving reaction. However theres also something called the Vant Hoff factor which complicates things. This basicallt says that even though something consists entirely of ions, some will remain together as an ionic solid in solution because the electrical attraction of the two ions will overcome the forces applied by the water trying to pull them apart. So for a reaction you might have a VHF of i = 1 which means that the solution is completely ionic and dissociates completely etc.

    Dunno if this helps, might be wrong but look up the Vant hoff thing, it might answer your question. if it doesnt, sorry :P

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