Iodate ion and Octet rule

'm trying to figure out why the oxidation state of the iodate ion is +5. The iodine atom has 7 electrons in its outermost shell (comprised of s and p sub-shells). Two oxygen atoms receive 2 electrons from iodine to obtain full valence shells (s2 p6) and only one electron goes to the other oxygen atom. This leaves iodine with a full sub-shell s2. Is this a deviation from the Octet rule?


And how is the charge on the iodate ion negative when the third oxygen requires an electron?




First of all I strongly advise you to go through the following link as it will make my answer more clear to you .


[Iodate ion](http://en.m.wikipedia.org/wiki/Iodate)



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> Two oxygen atoms receive 2 electrons from iodine to obtain full valence shells (s2 p6) and only one electron goes to the other oxygen atom.
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The bond between the iodine atom and oxygen atom is a [covalent bond](http://en.m.wikipedia.org/wiki/Covalent) . The electrons from the iodine atom are not given but shared .



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> This leaves iodine with a full sub-shell s2. Is this a deviation from the Octet rule?
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The two double bonded oxygens ( refer the structure in my link ) share in all 4 electrons and the 3rd oxygen shares a single electron . Iodine hence has more electrons than octet rule specified 8. This is why it violates the rule .



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> And how is the charge on the iodate ion negative when the third oxygen requires an electron?
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The third oxygen shares a single electron and hence has a negative charge on it which makes the overall molecule an anion with charge -1.


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