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Chem problem

  1. Nov 6, 2005 #1
    1. [1pt]

    The below reaction gives one ionic compound as a product.

    4Cu + O2 -->

    What is the name of the compound ?

    An example of the correct answer format would be lead(II) nitrate note the space

    Its going to be copper(I) oxide right, but I dont understand why?

    Also How many moles of the ionic compound are produced for the above reaction , would it be 4?
  2. jcsd
  3. Nov 6, 2005 #2


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    First write and balance the complete reaction. There can be no discussion of the second part before you do this.
  4. Nov 6, 2005 #3
    Isnt it

    4Cu + O2= 2Cu2O

    so it would be 2 moles, but why is it copper I oxide, not copper II oxide
  5. Nov 6, 2005 #4


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    It is easier to oxidize somethingto +1 (usually), than it is to oxidize it to +2. Taking that first electron away isnt so tough, but the second requires much more energy.
    Also, Copper (I) Oxide has a lower enthalpy of formation than Copper (II) Oxide, so it is more energy favorable for copper to oxidize to +1 than go all the way to +2.
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