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    So I'm told to suggest the chemical formula for Calcium Phosphate. I know it has calcium, phosphorus and oxygen and so I think of Ca(PO3)2 which is neutral and contains all of the required elements. Apparently this is calcium metaphosphate?!

    The answer is Ca3(PO4)2

    I assume it's about the bonding of the molecule but I don't know why. Many Thanks.
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    It is ionic: the calcium ion is 2+, the phosphate ion is 3-, balance the charges and you get Ca3(PO4)2.
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    (Original post by onefour)
    It is ionic: the calcium ion is 2+, the phosphate ion is 3-, balance the charges and you get Ca3(PO4)2.
    That doesn't make sense? Oxygen is 2- and according to your calculations, the overall charge on the molecule is -16
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    (Original post by Clarity Incognito)
    That doesn't make sense? Oxygen is 2- and according to your calculations, the overall charge on the molecule is -16
    She's right the phosphate ion i.e. PO43- has a charge of -3 not phosphorus itself
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    (Original post by EierVonSatan)
    She's right the phosphate ion i.e. PO43- has a charge of -3 not phosphorus itself
    Oops, didn't read the 'ion' after that. Yes, I understand why it works but why does Ca(PO3)2 not work? Calcium has +2 and (PO3)2 has -2
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    (Original post by Clarity Incognito)
    Oops, didn't read the 'ion' after that. Yes, I understand why it works but why does Ca(PO3)2 not work? Calcium has +2 and (PO3)2 has -2
    because phosphate is PO4 not PO3 :p:
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    (Original post by EierVonSatan)
    because phosphate is PO4 not PO3 :p:
    :sigh: I did not know lol, I only knew about the nomenclature. But can a phosphate not form as PO3? And do all phosphates have 4 oxygens?! Is there a general rule !
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    (Original post by Clarity Incognito)
    :sigh: I did not know lol, I only knew about the nomenclature. But can a phosphate not form as PO3? And do all phosphates have 4 oxygens?! Is there a general rule !
    it's nomenclature therefore quite complicated :p:

    http://en.wikipedia.org/wiki/Phosphinite

    Just remember that phosphate = PO43-
 
 
 
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