[NorthernLights]

Hello everyone,

I'm have difficulties understanding this ion, IO3- or Iodate.
When drawing the dot diagram i keep finding myself putting the extra electron on 1 of the O atoms creating a single bond while the other 2 O atoms have double bonds, because I thought oxygen is more electronegative then the iodine atom. Thinking its trigonal planar but going back to check my work in books and the net i find that its trigonal pyramidal with a lone pair on the iodine atom meaning the extra electron went to the I atom. Are my bonds wrong or whats happening? Any help would be much appreciated!

Thanks in advance.

[rabolisk]

When you draw it with the lone pair on the iodine, 2 oxygens double bonded to iodine, and 1 oxygen single bonded, what is the formal charge on each element? Also, if you were to put the extra electron on the single bonded oxygen, how many electrons do you have around it?

[NorthernLights]

Well I guess I'm dealing with all neutral atoms, I'm just having trouble understanding why the extra electron would not stay on the I central atom creating 3 double bonded O atoms, I might just confusing myself but any help would be great.

[rabolisk]

Now you're confusing me. The reason there wouldn't be 3 double bonded oxygen to iodine is because that would result in a negatively charged iodine as opposed to a negatively charged oxygen. As you said, electronegativity would favor oxygen bearing the negative charge, and the way you do this is by shifting the double bond over to the lone pair of the oxygen. Now you have a single bonded oxygen that bears the negative formal charge.