Sulfate

[Talia Leano 2H]

Why can sulfate have an extended octate?

[David Liu 1E]

sulfate/sulfur can have expanded d- orbitals; I'm not entirely sure why it happens, but because it has something to do with the d-orbitals elements in the second period can't have expanded octets, which is why sulfur is an example

[David Chibukhchian 2G]

Sulfur can have an expanded octet because it has valence electrons in the n=3 shell. This means it can basically utilize the 3d subshell when bonding, allowing it to have more than 8 electrons surrounding it in a Lewis Structure. Keep in mind that this would not work with the elements that don't fill up the n=3 shell. For example, nitrogen has electrons only up until the n=2 shell, which means it can't use the 3d subshell like sulfur can. I hope that answers your question!

[Madison Wong 3H]

I'm not positive, but basing it on quantum numbers, I think atoms in the d block have quantum number l=2 and thus can have 10 electrons since Ml can be 2,1,0,-1,-2 and 2 electrons can accompany each of those, which would be an expanded octet. I'm still a bit confused myself though.

[Inderpal Singh 2L]

As far as I know, it is because sulfate has d-orbitals. However, I am also still confused on why it is allowed an expanded octet. However, I think it may have something to do with the post being directly above mine ^ (-2,-1,0,1,2)

[Cassidy Cheng 1J]

Completely agree with the posts above me! But going off of that, elements in n=1 and n=2 can't have expanded octets bc according to the quantum numbers (i.e. n=2, l= 0, 1) they only have s and p orbitals, and they therefore only have 8 possible valence e-. Elements in n=3, however, have quantum numbers of n=3, l=0, 1, 2, and ml = -2, -1, 0, 1, 2, which means that they have s, p, and d orbitals. These elements therefore have the d orbitals (an extra 10 possible e-) that allows for the expanded octet.

[Chudi Onyedika 3A]

Sulfur is in the 3rd energy level, which gives it access to the d-orbital. The d-orbital gives room for more electrons.

[Colin Squire 3B]

Sulfur has access to the d-orbitals since it is in the third energy level. Because of this, it can hold more than 8 electrons, breaking the octet rule.

[AlbertGu_2C]

Any element past the 3rd period of the periodic table is able to have an expanded octet of electrons due to having access to more values of l.