Octet Exceptions

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Miguel Velasco 2J
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Octet Exceptions

Postby Miguel Velasco 2J » Mon Nov 06, 2017 8:46 pm

Are the only elements that adhere to the octet rule those with an energy level of 3 and below? Essentially those without access to the d orbital?

Lily Sperling 1E
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Re: Octet Exceptions

Postby Lily Sperling 1E » Mon Nov 06, 2017 8:55 pm

I believe anything on the periodic table past phosphorus can be an exception. Also important to note that Boron often has less than octet- for example: BF3.

nathansalce 3e
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Re: Octet Exceptions

Postby nathansalce 3e » Tue Nov 07, 2017 1:48 am

As far as I understand, the octet rule only applies to energy levels n=1, n=2. Any element in the n=3 energy or above may have an expanded octet and bond more than 4 times or have a combination of more than 8 electrons.

Michael Lee 2I
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Re: Octet Exceptions

Postby Michael Lee 2I » Thu Nov 09, 2017 2:15 pm

It's true that the expanded octet applies to those with an energy level of n=3 and higher. I think the most common ones we are going to see will be Phosphorus and Sulfur.

Alissa Stanley 3G
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Re: Octet Exceptions

Postby Alissa Stanley 3G » Wed Dec 06, 2017 1:39 pm

Could someone please summarize all the exceptions we need to be aware of for chemical bonds? I know of:
1. S, P, Xe, and the halogens can have an expanded octet
2. Be and B can have less than 8
3. Radicals are unpaired electrons

Is there anything I am missing?

diangelosoriano
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Re: Octet Exceptions

Postby diangelosoriano » Wed Dec 06, 2017 4:46 pm

Should we memorize all of the exceptions for the final?

aTirumalai-1I
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Re: Octet Exceptions

Postby aTirumalai-1I » Wed Dec 06, 2017 5:16 pm

Alissa Stanley 3G wrote:Could someone please summarize all the exceptions we need to be aware of for chemical bonds? I know of:
1. S, P, Xe, and the halogens can have an expanded octet
2. Be and B can have less than 8
3. Radicals are unpaired electrons

Is there anything I am missing?


Another thing to remember is that Hydrogen doesn't follow the octet rule either.

Alicia Beebe
Posts: 37
Joined: Fri Apr 06, 2018 11:01 am

Re: Octet Exceptions

Postby Alicia Beebe » Sun May 13, 2018 9:06 pm

I am also confused because, if these elements disobey the octet rule, aren't there several possible ways to write the structure? how do we know which one would be correct?

Chem_Mod
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Re: Octet Exceptions

Postby Chem_Mod » Sun May 13, 2018 10:14 pm

You also have to minimize the number of formal charges


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