Polar vs. Nonpolar

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

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

Polar vs. Nonpolar

Postby Lauren Lewis3L » Sun Nov 17, 2019 9:21 pm

Can explain what it means when it states in the book that it is nonpolar if it can "cancel out". I am just confused as to what is being cancelled when talking about atoms?

Sidharth D 1E
Posts: 98
Joined: Sat Aug 24, 2019 12:17 am

Re: Polar vs. Nonpolar

Postby Sidharth D 1E » Sun Nov 17, 2019 9:23 pm

They mean that the dipole-dipole vectors from two opposite atoms when added together equal to zero. A nonpolar molecule has a net dipole movement of zero.

ASetlur_1G
Posts: 101
Joined: Fri Aug 09, 2019 12:17 am

Re: Polar vs. Nonpolar

Postby ASetlur_1G » Sun Nov 17, 2019 9:23 pm

I think it means that even if a molecule has polar bonds, if the dipole moments cancel out (they are symmetrical), then the molecule is considered nonpolar.

Myka G 1l
Posts: 100
Joined: Fri Aug 30, 2019 12:17 am

Re: Polar vs. Nonpolar

Postby Myka G 1l » Sun Nov 17, 2019 9:23 pm

A molecule is also considered non polar if it has polar bonds and is symmetrical because the charges "cancel out" because they are distributed evenly among the molecule.

SVajragiri_1C
Posts: 115
Joined: Thu Jul 11, 2019 12:16 am

Re: Polar vs. Nonpolar

Postby SVajragiri_1C » Sun Nov 17, 2019 9:23 pm

For example, in the molecule CO2, the bond C-O itself is polar, but since the molecule CO2 is linear (O-C-O), the polarity of each bond cancels each other out due to the symmetric shape of the molecule. This concepts applies to most types of molecules.

Reagan Smith 1H
Posts: 50
Joined: Sat Jul 20, 2019 12:16 am

Re: Polar vs. Nonpolar

Postby Reagan Smith 1H » Sun Nov 17, 2019 9:25 pm

If the dipoles of two atoms are pointing in the same direction (such as the hydrogens in water) the dipoles do not cancel out and therefore water is polar, but if two vectors do cancel, the molecule is nonpolar.

Brianna Becerra 1B
Posts: 117
Joined: Fri Aug 02, 2019 12:16 am

Re: Polar vs. Nonpolar

Postby Brianna Becerra 1B » Sun Nov 17, 2019 9:25 pm

An example where the charges "cancel out" can be seen through the example BeCl2. Here, there is a negative charge on both of the cl which is on opposite ends meaning the arrows drawn will go away from each other making it so that the charges cancel out and it is now considered to be non-polar.

Brianna Becerra 1B
Posts: 117
Joined: Fri Aug 02, 2019 12:16 am

Re: Polar vs. Nonpolar

Postby Brianna Becerra 1B » Sun Nov 17, 2019 9:25 pm

An example where the charges "cancel out" can be seen through the example BeCl2. Here, there is a negative charge on both of the cl which is on opposite ends meaning the arrows drawn will go away from each other making it so that the charges cancel out and it is now considered to be non-polar.

ckilkeary 2G
Posts: 68
Joined: Fri Aug 09, 2019 12:16 am

Re: Polar vs. Nonpolar

Postby ckilkeary 2G » Sun Nov 17, 2019 9:27 pm

Nonpolar means that the dipole moments cancel out. In the case of CO2, because the oxygens (one each side) have the same strength of "pull" and effectively cancel each other out. Think of if as if there were two of the same person pulling at each side in tug of war. The rope in that game wouldn't be pulled in any direction because equal strength is pulling in opposite directions.


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