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Homework Help: Ionic nomenclator

  1. Feb 1, 2009 #1
    1. The problem statement, all variables and given/known data

    Write the formula for magnesium nitrate.

    2. The attempt at a solution

    Okay, so I get that I have to list the cation first and then the anion. I also understand that I have to take the charges into consideration and end up with a neutral compound. My question is why is the formula for magnesium nitrate

    Mg(NO3)2

    If Mg+2 N-3 and O[tex]^{3}_{-2}[/tex] to me it seems that O would have a total charge of -6 add the N charge and that's -9 while Mg has just +2. So this doesn't seem to equal out, plus I don't understand where the subscript 2 is from.

    Thanks for the help sorry if this is a simple question.
     
  2. jcsd
  3. Feb 1, 2009 #2

    symbolipoint

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    NITRATE has a charge of negative one;
    Nitrate has a charge of -1.

    Yes the oxygens each have associated charge of -2 each.

    One Mg ion has charge +2, so it needs 2 nitrates.
     
  4. Feb 1, 2009 #3
    Oh :blushing: thanks!
     
  5. Feb 1, 2009 #4

    symbolipoint

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    Could we put in a chart or a table in a message? Someone could clarify things like charge accounting for an ion very nicely using a table. I see no tags for creating a chart or table.
     
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