Repulsion strength and Bond Angles

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

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Kyle Harvey 4F
Posts: 45
Joined: Sat Aug 24, 2019 12:17 am

Repulsion strength and Bond Angles

Postby Kyle Harvey 4F » Sun Nov 17, 2019 7:08 pm

If two different molecules were to have the same shape, for example trigonal planar, but one molecule has a lone pair, would the bond angles between the central atom and the bonding atoms be different then the angles on the other molecule without the lone pair?

Shimei_2F
Posts: 100
Joined: Fri Aug 09, 2019 12:17 am

Re: Repulsion strength and Bond Angles

Postby Shimei_2F » Sun Nov 17, 2019 7:11 pm

Yes because the molecule with the lone pair would create repulsion that would alter the degrees of the bond angles.

Mariepahos4D
Posts: 50
Joined: Sat Sep 07, 2019 12:19 am

Re: Repulsion strength and Bond Angles

Postby Mariepahos4D » Sun Nov 17, 2019 7:11 pm

Yes, the one with the lone pair on the central atom would have increased repulsion because the electron repulsion of lone pair-bonding pair is greater than the electron repulsion in bonding pair to bonding pair, so the one with the central atom would have decreased bond angles.

saigorijavolu2k
Posts: 108
Joined: Sat Sep 28, 2019 12:15 am

Re: Repulsion strength and Bond Angles

Postby saigorijavolu2k » Sun Nov 17, 2019 7:12 pm

The repulsion would be different which will lead to a difference in bond angles

zoedfinch1K
Posts: 57
Joined: Thu Jul 25, 2019 12:16 am

Re: Repulsion strength and Bond Angles

Postby zoedfinch1K » Sun Nov 17, 2019 7:12 pm

If one of the molecules has a lone pair, there would be an electron repulsion between the lone pair and the other atoms in the molecule. This would make the resulting bond angle become smaller than the bond angle in the molecule with no lone pairs. This would also change the molecular structure from trigonal planar to bent.

Karyn How 1J
Posts: 50
Joined: Thu Jul 25, 2019 12:16 am

Re: Repulsion strength and Bond Angles

Postby Karyn How 1J » Sun Nov 17, 2019 7:14 pm

The bond angles would be slightly affected by the lone pair of the molecule if it was located on the central atom. The lone pair would cause more repulsion and slight bending. Also if the molecules were both trigonal planar, but one of the molecules had a lone pair then that molecule would be a bent shape instead which has a bond angle of less than 120.

Bradley Whitworth 4B
Posts: 54
Joined: Sat Jul 20, 2019 12:17 am

Re: Repulsion strength and Bond Angles

Postby Bradley Whitworth 4B » Sun Nov 17, 2019 7:15 pm

Yes, lone pairs create more repulsion so the angle between the 2 bonded atoms would be smaller and the two angles between the lone pair and the other two atoms would be bigger.

Justin Ko 4C
Posts: 17
Joined: Mon Sep 23, 2019 12:17 am

Re: Repulsion strength and Bond Angles

Postby Justin Ko 4C » Sun Nov 17, 2019 7:20 pm

Since the repulsion strength of lone pairs are stronger than the repulsion strength of bonding pairs, the molecule with the lone pair will have more bent bond angles

Abraham De Luna
Posts: 31
Joined: Sat Sep 14, 2019 12:16 am

Re: Repulsion strength and Bond Angles

Postby Abraham De Luna » Sun Nov 17, 2019 7:47 pm

Yes since the molecule with the lone pair would alter the degrees of the bond angles.

brennayoung
Posts: 51
Joined: Fri Sep 20, 2019 12:17 am

Re: Repulsion strength and Bond Angles

Postby brennayoung » Sun Nov 17, 2019 8:09 pm

Does anyone know if we need to have all of the bond angles of each shape memorized for Test 2? Also on that note if we do, do we need to know by how many degrees a lone pair would affect the angle or just that it would make it smaller due to electron repulsion pushing down the other atoms. Thanks!

Martina
Posts: 111
Joined: Thu Jul 25, 2019 12:16 am

Re: Repulsion strength and Bond Angles

Postby Martina » Sun Nov 17, 2019 8:10 pm

Yes, the lone pair repels the other bonds, causing the bond angle between them to be slightly less than what is expected.

brennayoung
Posts: 51
Joined: Fri Sep 20, 2019 12:17 am

Re: Repulsion strength and Bond Angles

Postby brennayoung » Sun Nov 17, 2019 8:16 pm

So we have to have all of the angles and possible lone pair induced angles memorized for test 2?

Lauren Lewis3L
Posts: 57
Joined: Wed Feb 20, 2019 12:16 am

Re: Repulsion strength and Bond Angles

Postby Lauren Lewis3L » Sun Nov 17, 2019 9:13 pm

brennayoung wrote:Does anyone know if we need to have all of the bond angles of each shape memorized for Test 2? Also on that note if we do, do we need to know by how many degrees a lone pair would affect the angle or just that it would make it smaller due to electron repulsion pushing down the other atoms. Thanks!

No, we don't need to know exactly how many degrees a lone pair would be effected but just know to label it on the test as greater than or less than the usual degree if the lone pair is present.


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