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I need Helps . Decomposition Reaction WE

  1. Jul 19, 2005 #1
    I need Helps..... Decomposition Reaction WE

    is this how you're supposed to write a decomposition reaction in a word equation?

    Copper (II) hydroxide decomposes with heat into the copper (II) oxide and water

    ....so then the water in this one would be a liquid right?
  2. jcsd
  3. Jul 19, 2005 #2
    Assuming it is under the correct temperature, the water will be water vapour, thus, a gas.

    The Bob (2004 ©)
  4. Jul 19, 2005 #3
    well we placed it into a hot water bath ....and constantly stirring it ... the color change so i guess it's gas ...right?
  5. Jul 20, 2005 #4
    What changed colour? The water?

    The Bob (2004 ©)
  6. Jul 20, 2005 #5
    The colour change tells you that the [tex]Cu(OH)_2[/tex] has changed somehow chemically. Since the most likely change is dehydration that is what you should reasonably assume is what happened. Basically the [tex]Cu(OH)_2[/tex] was probably hydrated to some extent and what happened is that you have removed this crystal water by heating the hydrate. [tex]Cu(OH)_2.nH2O(s) \xrightarrow{heat} Cu(OH)_2(s)~+~nH_2O(g)[/tex] describes this reaction.

    When the [tex]Cu(OH)_2[/tex] decomposes it leaves [tex]CuO[/tex] and [tex]H_2O[/tex]. The [tex]H_2O[/tex] will be released at temperatures of around [tex]185^{o}C[/tex] which is unlikely to be achieved in a hot water bath.
  7. Jul 26, 2005 #6
    oh I see now...thank you so much for your helps :)
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