Expanded Octets

Moderators: Chem_Mod, Chem_Admin

Posts: 74
Joined: Fri Sep 28, 2018 12:18 am

Expanded Octets

Postby paytonm1H » Thu Nov 22, 2018 4:00 pm

In the textbook, it states that in PCl5, the P atom expands its valence shell to ten electrons by using one d-orbital. Wouldn't the lowest energy be if the P atom used two d-orbitals with the two electrons having the same spin (Hund's Rule)? Why do they only fill one orbital?

Tarika Gujral 1K
Posts: 62
Joined: Fri Sep 28, 2018 12:27 am

Re: Expanded Octets

Postby Tarika Gujral 1K » Thu Nov 22, 2018 7:08 pm

A bond is only formed if it is energetically favorable, meaning that electrons in a bond have a lower energy then free electrons. Thus, it is more energetically favorable to fill 1 d orbital and have all electrons in a bond, as opposed to having electrons in a free orbital.

Return to “Octet Exceptions”

Who is online

Users browsing this forum: No registered users and 1 guest