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Qualitative analysis

  1. May 6, 2012 #1
    I'm just learning the basics, but I have a few questions.
    Why is it that there is no precipitate formed when calcium ions react with aqueous ammonia?
    Why is it that copper ions reactwith A little aqueous ammonia to form copper hydroxide precipitatinput dissolves in excess aqueous ammonia to form a solution???
    All help will be greatly appreciated thank you !
    Last edited: May 6, 2012
  2. jcsd
  3. May 6, 2012 #2
    Aqueous ammonia partially dissociate into NH4+ and OH- ions. So any calcium hydroxide formed will be a minute amount hence, it is able to dissolve in water leaving no precipitate. Copper (ii) hydroxide continues to react with the solution to form a deep blue solution.
  4. May 7, 2012 #3


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    Staff: Mentor

    Do you know what solubility product is? If so, compare solubility products of calcium hydroxide and copper hydroxide - which one is more soluble? Which one is easier to precipitate out of the solution?
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