expanded octet

Moderators: Chem_Mod, Chem_Admin

Alondra Juarez section 1E
Posts: 47
Joined: Fri Sep 29, 2017 7:03 am

expanded octet

Postby Alondra Juarez section 1E » Sun Jun 03, 2018 4:02 pm

How would we know when an atom has an expanded octet do we just have to know what are the exceptions by memory? if so what are they?

804991762_4A
Posts: 47
Joined: Fri Apr 06, 2018 11:04 am

Re: expanded octet

Postby 804991762_4A » Sun Jun 03, 2018 4:23 pm

To know if an atom has an expanded octet, you don’t have to memorize it. All you need to know is that an element that is in the 3rd period and beyond can have an expanded octet. So say you’ve done the Lewis structure for XeF4, it has 36 valence electrons and since fluorine can’t have double bonds, because it can’t have an expanded octet, you would put two lone pairs around Xe, in which Xe is allowed to have an expanded octet since its not in the 1st or 2nd row.

alexagreco1A
Posts: 34
Joined: Fri Apr 06, 2018 11:03 am

Re: expanded octet

Postby alexagreco1A » Sun Jun 03, 2018 4:23 pm

We know that only the elements that are in Group 3 or below can form an expanded octet, as they have unfilled d-orbitals, which Groups 1 and 2 do not have.

Chiara Berruto 1K
Posts: 29
Joined: Fri Apr 06, 2018 11:01 am

Re: expanded octet

Postby Chiara Berruto 1K » Mon Jun 04, 2018 7:23 pm

alexagreco1A wrote:We know that only the elements that are in Group 3 or below can form an expanded octet, as they have unfilled d-orbitals, which Groups 1 and 2 do not have.


This is absolutely correct. keep in mind that these elements dont necessarily always have an expanded octet and are completely happy with 8 electrons however this empty d-orbital (3d and on) allows them to accept more electrons if needed.

Alexander Hari 1L
Posts: 30
Joined: Wed Feb 14, 2018 3:02 am

Re: expanded octet

Postby Alexander Hari 1L » Mon Jun 04, 2018 8:44 pm

Elements in the 1st and 2nd period do not have access to the the d orbital which prevents them from having an expanded octet, therefore elements that are in the 3rd period and below have the potential to expand their octet.

Paywand Baghal
Posts: 32
Joined: Fri Apr 06, 2018 11:01 am

Re: expanded octet

Postby Paywand Baghal » Sat Jun 09, 2018 5:22 pm

Alexander Hari 1L wrote:Elements in the 1st and 2nd period do not have access to the the d orbital which prevents them from having an expanded octet, therefore elements that are in the 3rd period and below have the potential to expand their octet.


What is the extent of an extended octet?

Ignacio Ramirez 1J
Posts: 31
Joined: Tue Nov 14, 2017 3:02 am

Re: expanded octet

Postby Ignacio Ramirez 1J » Sat Jun 09, 2018 6:38 pm

The extent to what it can expand to, or if it can even have an extended octet depends on the element.

Chris Qiu 1H
Posts: 31
Joined: Fri Apr 06, 2018 11:04 am

Re: expanded octet

Postby Chris Qiu 1H » Sat Jun 09, 2018 7:10 pm

Anything past the third group can have an expanded octet.

MadelynNguyen1F
Posts: 59
Joined: Fri Apr 06, 2018 11:04 am

Re: expanded octet

Postby MadelynNguyen1F » Sun Jun 10, 2018 9:21 am

Any elements with an atomic number larger than 10 have access to the d orbital and can have an expanded octet.

Allen Chen 1J
Posts: 31
Joined: Wed Nov 15, 2017 3:04 am

Re: expanded octet

Postby Allen Chen 1J » Sun Jun 10, 2018 4:19 pm

Any elements with unfilled d orbitals can have expanded octet.

Maria Zamarripa 1L
Posts: 30
Joined: Fri Apr 06, 2018 11:05 am
Been upvoted: 1 time

Re: expanded octet

Postby Maria Zamarripa 1L » Sun Jun 10, 2018 5:39 pm

Elements that are in period 3 and beyond have the capacity to have an expanded octet. So if you have extra electrons, these elements would be able to hold more than 8 electrons.

Madeleine Farrington 1B
Posts: 32
Joined: Fri Apr 06, 2018 11:02 am

Re: expanded octet

Postby Madeleine Farrington 1B » Sun Jun 10, 2018 8:01 pm

Allen Chen 1J wrote:Any elements with unfilled d orbitals can have expanded octet.

Wait so if an element has a d-orbital but it is filled (ie As = [Ar]3d104s24p3) then it can't have an extended octet? Does this mean that only the transition metals can have an extended octet?

tmehrazar
Posts: 39
Joined: Fri Apr 06, 2018 11:04 am

Re: expanded octet

Postby tmehrazar » Sun Jun 10, 2018 9:23 pm

I know for sure non-metals have expanded octets so definitely not only transition metals. In the review today the TA said anything group 3 and lower can have an expanded octet so I think that's the most important thing to know.


Return to “Octet Exceptions”

Who is online

Users browsing this forum: No registered users and 2 guests