Bent shape and angles

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

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Luyan Zhang - 2D
Posts: 103
Joined: Sat Jul 20, 2019 12:16 am

Bent shape and angles

Postby Luyan Zhang - 2D » Fri Nov 15, 2019 12:41 am

Both VSEPR shape with the formula AX2E and AX2E2 have bent shape. What are the differences in their bond angles?

Jedrick Zablan 3L
Posts: 68
Joined: Sat Aug 17, 2019 12:17 am

Re: Bent shape and angles

Postby Jedrick Zablan 3L » Fri Nov 15, 2019 12:45 am

AX2E has a bond angle near 120 degrees while AX2E2 has a bond angle near 109.5 degrees.

KDang_1D
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Re: Bent shape and angles

Postby KDang_1D » Fri Nov 15, 2019 3:36 pm

The VSPER theory only gives qualitative, not quantitative descriptions of the shape of molecules, so although we know how the atoms are arranged, we cannot predict exactly what their angles will be.

AX2E will be less than 120 degrees, and AX2E2 will be less than 109.5 degrees. Those are the expected bond angles if all of the regions of electron density were atoms. But the lone pair-bonding pair repulsion is stronger than the bonding pair-bonding pair repulsion, so the atoms will be pushed closer together than these values.

Junxi Feng 3B
Posts: 52
Joined: Sat Sep 14, 2019 12:17 am

Re: Bent shape and angles

Postby Junxi Feng 3B » Fri Nov 15, 2019 3:39 pm

Both VSEPR shape with the formula AX2E and AX2E2 have bent shape. What are the differences in their bond angles?

I think AX2E2 will have a lower bond angle, because the extra lone pair will create a large repulsion which will push the atoms closer to each other and thus a smaller bond angle.

Arianna Perea 3H
Posts: 50
Joined: Thu Jul 25, 2019 12:17 am

Re: Bent shape and angles

Postby Arianna Perea 3H » Fri Nov 15, 2019 6:42 pm

So whenever the central atom has a lone pair accompanied by a bond on each side, the shape will be bent?

Aayush Patel 3B
Posts: 51
Joined: Thu Jul 25, 2019 12:17 am

Re: Bent shape and angles

Postby Aayush Patel 3B » Fri Nov 15, 2019 7:35 pm

If a molecule has 3 total domains, then one lone pair and two bonded atoms will result in a bent shape.

Louise Lin 2B
Posts: 97
Joined: Sat Aug 17, 2019 12:15 am

Re: Bent shape and angles

Postby Louise Lin 2B » Fri Nov 15, 2019 8:20 pm

If the central atom has two bonded pairs and either one or two lone pairs, this would result in the bent shape. The bond angle would be smaller if the central atom has two lone pairs because of electron repulsion.


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