expanded octet

[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?

[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.

[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.

[Chiara Berruto 1K]

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]

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]

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]

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

[Chris Qiu 1H]

Anything past the third group can have an expanded octet.

[MadelynNguyen1F]

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

[Allen Chen 1J]

Any elements with unfilled d orbitals can have expanded octet.

[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.

[Madeleine Farrington 1B]

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]

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.