Why can Xenon break the octet rule?

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Darren Nguyen 1F
Posts: 60
Joined: Sat Sep 14, 2019 12:15 am

Why can Xenon break the octet rule?

Postby Darren Nguyen 1F » Sun Nov 17, 2019 8:41 pm

There are so many exceptions how can I keep track of them all?

jeffreygong1I
Posts: 49
Joined: Thu Jul 11, 2019 12:15 am

Re: Why can Xenon break the octet rule?

Postby jeffreygong1I » Sun Nov 17, 2019 8:45 pm

I think elements can break the octet rule as long as they are n=3 or higher, since then they would have d-orbitals to put electrons in.

madawy
Posts: 81
Joined: Fri Aug 09, 2019 12:17 am

Re: Why can Xenon break the octet rule?

Postby madawy » Sun Nov 17, 2019 8:49 pm

According to the interweb, the Octet Rule is violated in these three scenarios:

When there are an odd number of valence electrons
When there are too few valence electrons
When there are too many valence electrons

Xenon is able to have an expanded octet, which can occur when the central atom with an expanded octet has an atomic number larger than 10 ( beyond neon ). When writing the Lewis Structure, you first place any extra electrons on the outside atoms. After the outside atoms have fulfilled the Octet Rule, and there are still extra electrons that need to be added, start with placing them as lone pairs on the central atom. If the central atom does not have a positive formal charge, do not go any further. Only if the central atom has a positive
charge should you move a lone pair from the outside atoms to share.

Michelle Shin 4B
Posts: 50
Joined: Thu Jul 25, 2019 12:17 am

Re: Why can Xenon break the octet rule?

Postby Michelle Shin 4B » Sun Nov 17, 2019 8:50 pm

In Xenon Tetrafluoride (XeF4), it breaks the octet rule to achieve a formal charge of zero in addition to it being higher than n=3.

Noah Canio 3C
Posts: 55
Joined: Wed Sep 18, 2019 12:20 am

Re: Why can Xenon break the octet rule?

Postby Noah Canio 3C » Sun Nov 17, 2019 9:20 pm

Any element within the third period and below on the periodic table will break the octet rule and will be able to have more electrons than eight. In addition, the first four elements won't have an completed octet (H, He, Li, Be) while the Boron's column of elements also doesn't need to have a completed octet.

SVajragiri_1C
Posts: 115
Joined: Thu Jul 11, 2019 12:16 am

Re: Why can Xenon break the octet rule?

Postby SVajragiri_1C » Sun Nov 17, 2019 9:28 pm

Like other elements with n=3 or higher, xenon has an empty d-orbital, specifically the 5d orbital, which can fill up with the extra electrons.

kevinolvera1j
Posts: 103
Joined: Fri Aug 02, 2019 12:15 am

Re: Why can Xenon break the octet rule?

Postby kevinolvera1j » Sun Nov 17, 2019 10:15 pm

In the typical example of xenon tetrafluoride, Xenon has 4 bonds and two lone pairs. This is possible since xenon is a large atom with valence electrons far away from its nucleus (relative to the noble gases that precede it) and fluorine is electronegative enough to pull away Xenons valence electrons allowing for an expanded octet to form.

J Medina 2I
Posts: 102
Joined: Wed Sep 25, 2019 12:17 am

Re: Why can Xenon break the octet rule?

Postby J Medina 2I » Sun Nov 17, 2019 10:23 pm

Xenon has d-orbitals, allowing it to store more electrons in its valence shell than atoms without any d-orbitals, like those that are at or come before 4s^2 .

Alice Chang 2H
Posts: 101
Joined: Fri Aug 30, 2019 12:18 am

Re: Why can Xenon break the octet rule?

Postby Alice Chang 2H » Sun Nov 17, 2019 10:26 pm

Elements with a d-orbital can allow for more than 8 electrons/break the octet rule! Xenon has a d-orbital so it can hold more electrons.


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