Types of Lone Pairs

(Polar molecules, Non-polar molecules, etc.)

Moderators: Chem_Mod, Chem_Admin

Posts: 24
Joined: Fri Sep 28, 2018 12:16 am

Types of Lone Pairs

Postby akroberts » Sun Nov 25, 2018 10:59 pm

What is the difference between axial and equatorial lone pairs, and do we need to be familiar with these?

Srikar_Ramshetty 1K
Posts: 64
Joined: Fri Sep 28, 2018 12:27 am

Re: Types of Lone Pairs

Postby Srikar_Ramshetty 1K » Sun Nov 25, 2018 11:04 pm

These lone pair names relate to where they are on the structure. An axial lone pair will be on one end of the axis while an equatorial lone pair will not be on the axis. The axis is the combination of the 2 surrounding atoms and the central atom, with a bond angle of 180 degrees similar to a x-axis or y-axis. I would recommend being familiar with them since the location of a lone pair can help you determine the correct molecular shape.

Hope this helps!

Carlos Gomez 3H
Posts: 29
Joined: Fri Sep 28, 2018 12:25 am

Re: Types of Lone Pairs

Postby Carlos Gomez 3H » Mon Nov 26, 2018 3:01 am

The difference between an equatorial and axial lone pair is that an axial lone pair is on the axis of the molecule, as seen most commonly in the octahedral, trigonal bipyramidal, see saw, and square pyramidal shapes. The axial lone pair strongly repels the electron pairs in the three equatorial bonds. The equatorial lone pair lies on the molecules equator, or the middle section that connects to the central atom and these strongly repel only the electron pairs in the two axial bonds. Knowing the difference will help in finding where a lone pair will have the least amount of repulsion strength when determining the shape.

Return to “Determining Molecular Shape (VSEPR)”

Who is online

Users browsing this forum: No registered users and 4 guests