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Help with test for anion in Copper Chloride

  1. Sep 2, 2005 #1
    I was given a small amount of Copper Chloride. When I brought my spatula(dirty ofcourse) the salt turned slightly green. Also when preparing the Sodium extract, I added 1 part CuCl<sub>2</sub> and 3 parts NaCO<sub>3</sub> and 3/4ths water. I stirred it slightly with the spatula, it turned black and my extract got prepared much before the others.

    I want to know what was in the spatula that made the extract production quicker coz. during my exams I could probably use it and finish it quickly.

    Also the china dish which had my extract became dirty so the teacher asked me to use dil. HCL to clean it. I put a little bit and like magic the dirt went away. I was so amazed. What is the equation of the reaction that happened?
    Why doesnt anyone use HCL for cleaning the kitchen utensils? :rolleyes:
  2. jcsd
  3. Sep 2, 2005 #2


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    I would imagine that the HCl protonated the compound so that it was extracted into the water.

    You might want to be a bit more clearer with the first paragraph.
  4. Sep 3, 2005 #3
    perhaps you ever so slightly hydrated the cupricchloride with the dirty spatula which would be why it turned green. When you added the [tex]NaCO_3[/tex] to the [tex]CuCl_2[/tex] you made [tex]CuCO_3[/tex] Which is black. When you then added the hydrochloric acid you converted the [tex]CuCO_3[/tex] back to [tex]CuCl_2[/tex] which is pretty soluble.

    People do not use hydrochloric acid to clean their glassware because it does not really clean a lot of things very well. Only oxides and carbonates will really react with it. For organic residues you would need something much stronger, like a strong oxidizer such as [tex]H_2SO_5[/tex] or [tex]Mn_2O_7[/tex] which are usually created in situ by mixing sulfuric acid with hydrogenperoxide or potassiumpermanganate.
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