Strength of Repulsion

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Frederick Keith_4C
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Joined: Thu Sep 26, 2019 12:19 am

Strength of Repulsion

Postby Frederick Keith_4C » Sun Nov 17, 2019 1:23 pm

I see that the strengths of repulsion are in order if lone pair-lone pair > lone pair-atom > atom-atom, but I don't really understand why this is the case. Why do lone pairs have a more strongly repelling effect compared to bonded electrons? If could someone could explain this to me, that would be great.

Aiden Metzner 2C
Posts: 104
Joined: Wed Sep 18, 2019 12:21 am

Re: Strength of Repulsion

Postby Aiden Metzner 2C » Sun Nov 17, 2019 1:26 pm

Lone pairs have a stronger repulsion because they are two negatively charged electrons. So they push repulse each-other a lot more then an electron and an atom would repulse because atoms don't have as strong of a negative charge if they are even charged at all. Just remember that lone-pairs are two electrons so they have strong negative charges.

Ruby Tang 2J
Posts: 102
Joined: Fri Aug 30, 2019 12:15 am

Re: Strength of Repulsion

Postby Ruby Tang 2J » Sun Nov 17, 2019 1:28 pm

The electron cloud of a lone pair is dispersed over a larger area than that of a bonding pair, because while a bonding pair is held in place by two atoms, a lone pair is only held in place by one. This means that there is only one nucleus's positive charge drawing in and localizing the electron cloud of a lone pair, whereas there would be two for a bonding pair. Hope this helps!

Naji Sarsam 1F
Posts: 104
Joined: Sat Aug 17, 2019 12:18 am

Re: Strength of Repulsion

Postby Naji Sarsam 1F » Sun Nov 17, 2019 1:31 pm

This is because lone pair electrons take up more volume with their electron clouds as they are only being held by one atom's nucleus. Bonding electrons are confined to a smaller volume as they feel the influence of two atoms' nuclei, confining them to a smaller space.

Thus, it is not that lone pair electrons inherently have different repulsion strengths than bonding electrons. Rather, lone pair electrons need more space for their electron clouds than bonding electrons do. Thus, lone pair electrons repel each other further away to make room for their larger electron clouds, in comparison to bonding electrons which don't need to repel each other as far.

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Joined: Sat Sep 14, 2019 12:15 am

Re: Strength of Repulsion

Postby ranqiao1e » Fri Nov 22, 2019 10:23 pm

Because they occupy a bigger area than bonds do

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