Octet rule

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MinjooPark_3I
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Octet rule

Postby MinjooPark_3I » Sun Nov 29, 2020 5:52 pm

Hi! So I was doing the sapling workbook problems and realized that for 2E.19, most of the central atoms in this problem did not fulfill the octet rule. Are Be, B, and Sn exceptions to the octet rule or does it only work in this case? Thank you for any help!

dana hu 1B
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Re: Octet rule

Postby dana hu 1B » Sun Nov 29, 2020 6:04 pm

Expectations of breaking the octet rule:
An electron or molecule which contains unpaired electrons in its outermost shell or valence shell is considered as free radical.
Elements like hydrogen, lithium, helium do not obey the octet rule.
Another exception of the octet rule is transition elements. Due to the presence of d-orbitals, they can hold 18 electrons in its outermost shell.
Hope this helps!

Arnav Saud 2C
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Re: Octet rule

Postby Arnav Saud 2C » Sun Nov 29, 2020 6:10 pm

If I'm correct, for this class, the main incomplete octet elements you need to know are Be, B, and Al. The textbook section 2C.3 has a good explanation on the incomplete octet elements as well.

David Jen 1J
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Re: Octet rule

Postby David Jen 1J » Sun Nov 29, 2020 6:31 pm

Hydrogen is also an exception to the octet rule!

MinjooPark_3I
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Re: Octet rule

Postby MinjooPark_3I » Tue Dec 01, 2020 4:56 pm

Thank you to the people that replied! I will be checking the textbook pages for more info!

Akshata Kapadne 2K
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Re: Octet rule

Postby Akshata Kapadne 2K » Tue Dec 01, 2020 6:23 pm

Any element from period 3 and onward can have expanded octets because they have d-orbitals that can accommodate additional electrons. Additionally, boron and aluminum have incomplete octets. Lastly, hydrogen, helium, lithium, and beryllium don't have complete octets. I believe those are the only exceptions we have to know. I hope this helps!

abby hyman
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Re: Octet rule

Postby abby hyman » Tue Dec 01, 2020 6:46 pm

The exceptions for the octet rule include examples such as SF6 where Sulfur can accommodate more than 8 valence electrons and BCl3 where Boron has less than 8 electrons in its valence shell.

Arnav Saud 2C
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Re: Octet rule

Postby Arnav Saud 2C » Sat Dec 12, 2020 11:48 pm

For the purposes of this class, the p block elements that have an expanded octet are P, S, and Cl. H, He, Li, Be, B, and Al can have an incomplete octet.

Joshua Chung 2D
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Re: Octet rule

Postby Joshua Chung 2D » Sun Dec 13, 2020 1:15 pm

Think of it as the third row p-block elements can have expanded octets, and B, Be, Li, He, and H can have less than an octet.

Malakai Espinosa 3E
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Re: Octet rule

Postby Malakai Espinosa 3E » Sun Dec 13, 2020 1:17 pm

Some of the elements that don't follow the octet rule are B, Be, and Al.

Ke Huang 2G
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Re: Octet rule

Postby Ke Huang 2G » Tue Dec 15, 2020 12:03 am

I was having this question too. Thanks for asking!

Chenning Yang Dis3l
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Re: Octet rule

Postby Chenning Yang Dis3l » Tue Dec 15, 2020 10:40 am

Thank you for the post!

Brandon Carris
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Re: Octet rule

Postby Brandon Carris » Tue Dec 15, 2020 6:29 pm

I had this question too thanks for the answers everyone!


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