VSEPR and polarity

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

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Guzman_1J
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Joined: Wed Sep 18, 2019 12:16 am

VSEPR and polarity

Postby Guzman_1J » Sun Dec 08, 2019 12:33 am

Can anyone tell me the general rules about polarity when it comes to shape? I remember Lyndon mentioning during review that certain shapes are always polar unless they're all the same element but was not able to catch everything he said.

Nohemi Garcia 1L
Posts: 103
Joined: Fri Aug 02, 2019 12:15 am

Re: VSEPR and polarity

Postby Nohemi Garcia 1L » Sun Dec 08, 2019 12:35 am

Tetrahedral I believe is one of these examples. It tends to be polar but in cases such as CH4, the structure become neutral. This is because all of the surrounding atoms are the same and their dipoles "cancel out."

Jacey Yang 1F
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Joined: Fri Aug 09, 2019 12:17 am

Re: VSEPR and polarity

Postby Jacey Yang 1F » Sun Dec 08, 2019 1:22 am

A molecule is polar when the central atom has lone pairs and the atoms attached aren’t the same, so the dipoles don’t cancel.

Guzman_1J
Posts: 72
Joined: Wed Sep 18, 2019 12:16 am

Re: VSEPR and polarity

Postby Guzman_1J » Sun Dec 08, 2019 1:30 am

Jacey Yang 3I wrote:A molecule is polar when the central atom has lone pairs and the atoms attached aren’t the same, so the dipoles don’t cancel.

Is this for all molecules?

Anna Heckler 2C
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Joined: Wed Sep 18, 2019 12:18 am

Re: VSEPR and polarity

Postby Anna Heckler 2C » Sun Dec 08, 2019 1:51 am

Basically the only time it will be neutral is when all four atoms in a tetrahedral molecule are the same atom. Lone pairs and varying atoms creates dipoles that affect the net dipole, and therefore polarity, of the molecule.

Guzman_1J
Posts: 72
Joined: Wed Sep 18, 2019 12:16 am

Re: VSEPR and polarity

Postby Guzman_1J » Sun Dec 08, 2019 2:23 am

Nohemi Garcia 1I wrote:Tetrahedral I believe is one of these examples. It tends to be polar but in cases such as CH4, the structure become neutral. This is because all of the surrounding atoms are the same and their dipoles "cancel out."

Is this the only shape with this characteristic?

William Francis 2E
Posts: 101
Joined: Wed Sep 18, 2019 12:20 am

Re: VSEPR and polarity

Postby William Francis 2E » Sun Dec 08, 2019 2:42 am

Linear, trigonal planar, tetrahedral, trigonal bipyramidal, octahedral, and square planar shapes are symmetrical which means that molecules of these shapes are nonpolar if all atoms bonded to the central atom are the same.

Guzman_1J
Posts: 72
Joined: Wed Sep 18, 2019 12:16 am

Re: VSEPR and polarity

Postby Guzman_1J » Sun Dec 08, 2019 2:58 am

William Francis 3C wrote:Linear, trigonal planar, tetrahedral, trigonal bipyramidal, octahedral, and square planar shapes are symmetrical which means that molecules of these shapes are nonpolar if all atoms bonded to the central atom are the same.

Is it a general rule that all atoms must be the same? If there is a molecule that has different atoms but the dipole moments point opposite each other, they still would not cancel out so the molecule would still be polar because the atoms are not the same?

Miriam Villarreal 1J
Posts: 105
Joined: Sat Aug 17, 2019 12:16 am

Re: VSEPR and polarity

Postby Miriam Villarreal 1J » Sun Dec 08, 2019 11:15 pm

Trigonal Planar, Linear, Square Planar, and Tetrahedral (if it's the same elements) will be non polar since dipoles cancel, but the rest of the shapes will be polar.


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