lone pairs

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

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Lauren Bui 1E
Posts: 54
Joined: Sat Jul 20, 2019 12:15 am

lone pairs

Postby Lauren Bui 1E » Sun Nov 17, 2019 3:32 pm

why do lone pairs have to be across from each other if there are multiple?

Posts: 120
Joined: Wed Sep 18, 2019 12:20 am

Re: lone pairs

Postby Shanzey » Sun Nov 17, 2019 3:39 pm

I believe that we put the lone pairs across from each other in order to minimize electron repulsion for octahedral shapes. For instance, Dr. Lavelle used the example of XeF4 in lecture and placed the lone pairs opposite from each other because that is the shape with the least amount of repulsion for that octahedral shape.

Katheryne N 3G
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Joined: Wed Nov 14, 2018 12:22 am

Re: lone pairs

Postby Katheryne N 3G » Sun Nov 17, 2019 3:50 pm

In the case of a molecule such as XeF4 (Xenon Tetrafluoride) that has 6 regions of electron density, including 2 lone pairs on Xe and 4 F atoms bonded to Xe, you want a shape of the molecule that would result in the least amount of repulsion between the higher regions of electron density and so the lone pairs would need to be as far away from each other as possible. In the case of this molecule, it would be on opposite sides of the central atom.

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Joined: Wed Feb 27, 2019 12:17 am

Re: lone pairs

Postby Ayushi2011 » Sun Nov 17, 2019 4:28 pm

Lone pair-lone pair electron repulsion is the highest, so they need to be placed away from each other as we want minimum repulsion for most stability.

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