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expanded octet

Posted: Sun Jun 03, 2018 4:02 pm
by Alondra Juarez section 1E
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?

Re: expanded octet

Posted: Sun Jun 03, 2018 4:23 pm
by 804991762_4A
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.

Re: expanded octet

Posted: Sun Jun 03, 2018 4:23 pm
by alexagreco1A
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.

Re: expanded octet

Posted: Mon Jun 04, 2018 7:23 pm
by Chiara Berruto 1K
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.

Re: expanded octet

Posted: Mon Jun 04, 2018 8:44 pm
by Alexander Hari 1L
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.

Re: expanded octet

Posted: Sat Jun 09, 2018 5:22 pm
by Paywand Baghal
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?

Re: expanded octet

Posted: Sat Jun 09, 2018 6:38 pm
by Ignacio Ramirez 1J
The extent to what it can expand to, or if it can even have an extended octet depends on the element.

Re: expanded octet

Posted: Sat Jun 09, 2018 7:10 pm
by Chris Qiu 1H
Anything past the third group can have an expanded octet.

Re: expanded octet

Posted: Sun Jun 10, 2018 9:21 am
by MadelynNguyen1F
Any elements with an atomic number larger than 10 have access to the d orbital and can have an expanded octet.

Re: expanded octet

Posted: Sun Jun 10, 2018 4:19 pm
by Allen Chen 1J
Any elements with unfilled d orbitals can have expanded octet.

Re: expanded octet

Posted: Sun Jun 10, 2018 5:39 pm
by Maria Zamarripa 1L
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.

Re: expanded octet

Posted: Sun Jun 10, 2018 8:01 pm
by Madeleine Farrington 1B
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?

Re: expanded octet

Posted: Sun Jun 10, 2018 9:23 pm
by tmehrazar
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.