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Peroxide vs. dioxide

  1. Mar 18, 2010 #1

    What is the difference between peroxide and dioxide? Why isn't CO2 carbon peroxide?

    I'm finding this important in Redox rxns but have not found a way to differentiate the 2 or actually define them.

    Any help appreciatted!

  2. jcsd
  3. Mar 18, 2010 #2


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    Look up the definition of "peroxide" and pay special attention to the O-O
  4. Mar 18, 2010 #3
    Thanks for being so quick!

    But all I can find is a Wikipedia entry and have gleamed that peroxides are cations 2- as opposed to neutral O2 molecules.....right?

    So how does one determine if it's a peroxide? NaO2, LiO2, CO2 etc....is it determined by the charge? So Li2O2 a peroxide and LiO2 a dioxide?

    I think I got it! Right?

  5. Mar 18, 2010 #4


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    What are the characteristics of peroxides? Are they oxidizers, and if so, why? Is CO2 an oxidizer? If not, why not?
  6. Mar 20, 2010 #5
    In beginning chemistry at least, you can look at it this way:

    You can tell by the charge. Peroxide is O22- as in Li2O2.
    The two oxygens in NaO2, however, are not part of peroxide because that ion has a 1- charge: O2- which is superoxide.
    In a covalent compound such as CO2, the two oxygens would be called dioxide.
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