Can you look at this image and tell me how clo3- does NOT violate the octet rule?

S

Shella

New member
http://en.wikipedia.org/wiki/File:Chlorate-resonance-2D.png

I don't understand. The Cl has 7 electrons but yet it still states it's correct when it's suppose to be 8. Am I not seeing something right?
i know that. i mean for the octet rule about it wanting 8 or something...
 
I would talk to your professor/teacher. This is a very poor example. ClO3- does violate the octet rule in actuality, because it has access to and hybridized d orbitals.

Don't look at other websites, use the methodology you were taught by your professor to draw the lewis structure.

1) Least electronegative atom goes in the middle, which is Cl.

2) Add together all of the electrons. Cl=7, 3O=18, and the negative charges means it has an extra electron (1). So you have 26 total

3) Draw all other species single bonded to Cl. (three sigma bonds=6e-)

4) Fill the rest with lone pairs. (20e- left to place in lone pairs)

Now you should have Cl in the middle, sigma bonded to three oxygens. The oxygens should have 3 lone pairs and Cl should have one lone pair.
 
Actually it has 12 electrons that it is holding, 7 from itself, 2 from each of the double bonded oxygens and one from the other, and one from the single bond.

This is possible because Cl can expand its octet, as can all atoms after Sulfur in the periodic table. This is because it can place extra electrons in the 3d subshell, which has not yet been filled. Sorry I can't be more specific than that, as I don't actually know the exact reason for this myself, but I assume it has something to do with it being unstable when the 3rd shell being filled but the 3d sub-shell being left empty.
 
The octet rule is a generic rule that doesn't apply for all molecules out there. You're seeing it right. The chlorate ion has a -1 charge. When it combines with something like a proton (H+) it becomes neutral and then satisfies the full octet rule.

Polyatomic ions have a charge that needs to be satisfied in order to bond with something.
 
Since chlorine is covalently bonded to oxygen, you count one of the two shared electrons between O-Cl and add that number to the number of lone electrons (or e- pairs).
 
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