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Homework Help: Question about a base

  1. Apr 27, 2006 #1
    NaOH and other hydroxide bases are ionic or molecular substances?

    In water, they will dissociate into a cation and one or more hydroxide ions or ionize, forming those ions?
  2. jcsd
  3. Apr 27, 2006 #2


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    not all hydroxides are soluble in water
  4. Apr 27, 2006 #3
    GCT, that is not the point, altough it is an interesting information.

    You did not answer my question or I hadn't express myself clear?
    It is basically: NaOH dissociates or ionizes in water?
  5. Apr 27, 2006 #4


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    Sodium Hydroxide (NaOH) [and other Hydroxide substances] are ionic as they are made up of ions.

    In Sodium Hydroxide, there is one Na+1 ion for every 1 Hydroxide (OH-) ion to form an over all neutral ionic compound.

    In water, the two ions dissassociate (completely in the case of NaOH) to form an aqueous solution of Na+ and OH-.
  6. Apr 27, 2006 #5
    Thank you, mrjeffy321!
    And a general acid, let's say HA, is also made up of ions?
  7. Apr 27, 2006 #6


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    Acids are a little bit tricky-er than Hydroxides.

    For example, take Hydrochloric acid....,
    Hydrochloric acid is made by dissolving Hydrogen Chloride gas in water, when this happens, the HCl breaks up into ions in solution forming the acid solution, however, HCl gas is not ionic, the H and Cl atoms are held together with a polar covalent bond.

    Another example,
    Sulfuric acid is an aqueous solution of H2SO4, which is held together through the attractions between the H+ and SO4-2 ions. When H2SO4 is put into solution, since it is a strong acid, it will easily dissassociate completely into H+ and HSO4- ions, and then partially dissassociate again into H+ and SO4-2 ions (HSO4- is not as strong of an acid as H2SO4).

    Another example,
    Hydroflouric acid (HF) is made up of Hydrogen Flouride, a very ionic substance. Since Hydroflouric acid is a weak acid (because it isnt a strong acid) When HF is dissolved in water, only some of it dissassociates into ions.

    But yes, for a very general case, acids are usually made up of ions since when they are dissolved, they will liberate H+ ions into solution, lowering the pH.
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