polar v nonpolar molecules

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

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Danielle DIS2L
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polar v nonpolar molecules

Postby Danielle DIS2L » Sun Nov 29, 2020 11:01 pm

How would you differentiate polar and nonpolar molecules?

705512695
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Re: polar v nonpolar molecules

Postby 705512695 » Sun Nov 29, 2020 11:04 pm

Non polar molecules are symmetric while polar molecules are asymmetric. Polar molecules have a electronegativity difference between the bonded atoms. while Nonpolar molecules electrons are shared equal between atoms.

AdilaAhmed3I
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Re: polar v nonpolar molecules

Postby AdilaAhmed3I » Sun Nov 29, 2020 11:05 pm

So an easy way to determine polarity is by seeing is the molecule is "balanced" or "lopsided". If it is a molecule like CCl4 where all the atoms surrounding the C are Cl, it is balanced and nonpolar. This is because the electronegativity between the Cl and C (the Cl-C bond) are the same all the way around the atom.
If it was a molecule like CH3Cl, it would be polar because there is a different electronegativity which would alter the dipole moments. The C-Cl bond has a different electronegativity than the C-H bond so it is "lopsided" and polar.

Taha 2D
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Re: polar v nonpolar molecules

Postby Taha 2D » Sun Nov 29, 2020 11:05 pm

Polar molecules occur when there is an electronegativity difference between the bonded atoms. Nonpolar molecules occur when electrons are shared equal between atoms of a diatomic molecule or when polar bonds in a larger molecule cancel each other out.

Annie Tong 2G
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Re: polar v nonpolar molecules

Postby Annie Tong 2G » Sun Nov 29, 2020 11:07 pm

Polarity depends on the electronegativity difference present between two bonded atoms in a molecule. A dipole will form and the molecule will gain partial positive and negative charges. If a molecule has certain areas with high dipole moments and other areas with low dipole moments, and those moments are distributed unevenly, it's polar.

Mina Tadros 3L
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Re: polar v nonpolar molecules

Postby Mina Tadros 3L » Sun Nov 29, 2020 11:14 pm

Polar molecules are molecules that have dipoles that do not cancel. Nonpolar molecules have dipoles that do cancel. Also, if there are differences in electronegativity because the atoms bound to the central atom are not uniform, then it will be a polar molecule.

Maryeli Garay 2H
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Re: polar v nonpolar molecules

Postby Maryeli Garay 2H » Sun Nov 29, 2020 11:16 pm

If you want to tell by just looking at a structure I’d say look for symmetry. Nonpolar molecules are symmetric and polar molecules are asymmetric.

Jaden Ji 2K
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Re: polar v nonpolar molecules

Postby Jaden Ji 2K » Sun Nov 29, 2020 11:18 pm

Polar molecules are often asymmetric and consequently have dipole moments that do not cancel out, while nonpolar molecules are symmetrical which causes the dipole moments to cancel each other out.

Sydney Jensen 3L
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Re: polar v nonpolar molecules

Postby Sydney Jensen 3L » Sun Nov 29, 2020 11:50 pm

When there is a large electronegativity difference, then the molecule would be considered polar. The most electronegative elements are fluorine, oxygen, and nitrogen

Megan ODonnell 3F
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Re: polar v nonpolar molecules

Postby Megan ODonnell 3F » Sun Nov 29, 2020 11:53 pm

Usually I first try to determine through symmetry, if the shape of the molecule and the bond angles are the same throughout, it is most likely nonpolar. However compare and contrast the bonded atoms to the central atom, an atom with a fluorine bonded on one side and a hydrogen bonded on the other side, even if symmetrical in shape will have stronger dipole movement toward the fluorine and thus be polar.

Gabriel Nitro 1E
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Re: polar v nonpolar molecules

Postby Gabriel Nitro 1E » Mon Nov 30, 2020 8:32 am

Hi,

Polar molecules tend to have polar bonds which are in an asymmetric molecule, while nonpolar molecules either have only nonpolar bonds or have polar bonds which cancel out.

Hope this helps! :)

Mari Williams 1K
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Re: polar v nonpolar molecules

Postby Mari Williams 1K » Mon Nov 30, 2020 10:42 am

Polar molecules have polar bonds whose dipoles do NOT cancel out, while nonpolar molecules either have all nonpolar bonds or polar bonds that do cancel each other out.

Juwan_Madaki_3K
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Re: polar v nonpolar molecules

Postby Juwan_Madaki_3K » Thu Dec 03, 2020 10:53 am

I know that Professor Lavelle said we wouldn't be drawing vectors, but I still use them to determine if something is polar or nonpolar. A polar molecule's vectors/dipoles DON'T cancel and a non polar molecule's dipoles/vectors DO cancel. I also look at the electronegativity values to help. Typically, a non polar molecules' electronegativity difference is .4 and less. However, in the case that we aren't provided with an electronegativity chart, I would stick to looking at dipoles/vectors.

Annette Fishman
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Re: polar v nonpolar molecules

Postby Annette Fishman » Thu Dec 03, 2020 12:36 pm

Polar molecules occur when there is an electronegativity difference between the bonded atoms, whereas nonpolar molecules occur when electrons are shared equal between atoms of a diatomic molecule or when polar bonds in a larger molecule cancel each other out.

Jason Knight - 1F
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Re: polar v nonpolar molecules

Postby Jason Knight - 1F » Thu Dec 03, 2020 1:16 pm

Polar molecules are present when there is an electronegativity difference amongst the bonded atoms. For example, Ammonia is a polar molecule because there is a difference in the electronegativity between the atoms. Non-polar molecules have no charge and no difference in electronegativity.

apurva-3E
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Re: polar v nonpolar molecules

Postby apurva-3E » Thu Dec 03, 2020 1:40 pm

Calculate the polarity vectors and see if they cancel out. Must draw lewis structure.

Lorena_Morales_1K
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Re: polar v nonpolar molecules

Postby Lorena_Morales_1K » Sat Dec 05, 2020 8:39 pm

Danielle DIS 3K wrote:How would you differentiate polar and nonpolar molecules?


Polar molecules occur when there is an electronegativity difference between the bonded atoms. Nonpolar molecules occur when electrons are shared equal between atoms of a diatomic molecule or when polar bonds in a larger molecule cancel each other out.

Yolanda_Xing_3A
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Re: polar v nonpolar molecules

Postby Yolanda_Xing_3A » Sun Dec 06, 2020 8:11 am

polar molecules are usually symmetrical while non polar isn't

305614361
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Re: polar v nonpolar molecules

Postby 305614361 » Sun Dec 06, 2020 5:24 pm

Polar molecules occur when there is an electronegativity difference between the bonded atoms. Nonpolar molecules occur when electrons are shared equally between atoms of a diatomic molecule or when polar bonds in a larger molecule cancel each other out

Emma_Barrall_3J
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Re: polar v nonpolar molecules

Postby Emma_Barrall_3J » Sun Dec 06, 2020 5:27 pm

If there is a net dipole moment, the molecule is polar.

Jaclyn Schwartz 1I
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Re: polar v nonpolar molecules

Postby Jaclyn Schwartz 1I » Sun Dec 06, 2020 6:39 pm

non-polar molecules are symmetrical and have no dipole movement. Polar molecule are non-symmetrical and have dipole movement.

Yuehan_Wu_3K
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Re: polar v nonpolar molecules

Postby Yuehan_Wu_3K » Sun Dec 06, 2020 6:52 pm

Non polar molecules are symmetric with no unshared electrons. Polar molecules are asymmetric, either containing lone pairs of electrons on a central atom or having atoms with different electronegativities bonded.

Queena Chu 3E
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Re: polar v nonpolar molecules

Postby Queena Chu 3E » Sun Dec 06, 2020 7:00 pm

Polar compounds have a net dipole as a result of polar bonds that are arranged asymmetrically. Nonpolar compounds can either entirely share their electrons, or they can have symmetrical polar bonds that end up canceling out any sort of net dipole.

Shalyn Kelly 3H
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Re: polar v nonpolar molecules

Postby Shalyn Kelly 3H » Sun Dec 06, 2020 7:09 pm

Hi! If you're having trouble remembering which one is symmetrical, I use:
Assuming symmetrical is the norm: polar molecules are typically asymmetrical, so I think of how they like to be "different" or have "polarizing opinions" hence the asymmetrical shape; nonpolar molecules are symmetrical, so I think of how they like to remain neutral (dipoles cancel out) and don't like to cause a fuss, hence the nonpolar aspect.
If this makes sense to you, I hope it helps.

Madeline Marron 1I
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Re: polar v nonpolar molecules

Postby Madeline Marron 1I » Sun Dec 06, 2020 7:54 pm

This was super duper helpful, thank you guys!

Arnav Saud 2C
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Re: polar v nonpolar molecules

Postby Arnav Saud 2C » Sun Dec 06, 2020 7:55 pm

The main thing when looking at these kinds of molecules is to figure out what atoms are bonded to each other, and potential dipole moments. Generally, if a molecule is not asymmetric and the atoms bonded to the central atom are different, then the molecule is polar.
An example of each is H2O with its bent angular formation, which causes it to be polar.
Another example is CCl4 and CCl3H. CCl4 is nonpolar while CCl3H is polar because the dipole moments are not canceled out.

Bai Rong Lin 2K
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Re: polar v nonpolar molecules

Postby Bai Rong Lin 2K » Sun Dec 06, 2020 10:21 pm

Danielle DIS 3K wrote:How would you differentiate polar and nonpolar molecules?

One of the most common way to differentiate the two is its electronegativity between the bonding molecules.

Joshua Chung 2D
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Re: polar v nonpolar molecules

Postby Joshua Chung 2D » Sun Dec 06, 2020 10:44 pm

First, you gotta determine the differences in electronegativity between the individual atoms. If none exist or if they cancel each other out, then the molecule is nonpolar. If there is a noticeable direction of electronegativity difference, then the molecule is polar.

Susan Chamling 1F
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Re: polar v nonpolar molecules

Postby Susan Chamling 1F » Sun Dec 06, 2020 11:05 pm

Polar molecules are when the bonded atoms have an electro negativity difference and asymmetry is observed where dipole forces are not canceled out. On the other hand nonpolar molecules are when electrons are shared equally among the atoms of the molecule or when the dipole forces cancel one another out.

Maddie Turk Disc 2J
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Re: polar v nonpolar molecules

Postby Maddie Turk Disc 2J » Tue Dec 08, 2020 10:46 am

Is the rule that nonpolar molecules are symmetric and polar molecules are asymmetric always true or are there exceptions?

apurva-3E
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Re: polar v nonpolar molecules

Postby apurva-3E » Tue Dec 08, 2020 2:14 pm

So you want to determine the molecular shape using VSEPR geometry and identify how electronegative elements are arranged. This can give you a glimpse into whether a compound is polar or not.


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