Dipole Moments and Polarity

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MichelleKaku1H
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Dipole Moments and Polarity

Postby MichelleKaku1H » Sun Dec 03, 2017 4:45 pm

Can someone please clarify how to find/determine the dipole of a molecule and how you can find polarity with that?

Mika Sonnleitner 1A
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Re: Dipole Moments and Polarity

Postby Mika Sonnleitner 1A » Sun Dec 03, 2017 5:01 pm

Dipole moments occur between two bonded atoms of different electronegativities. For example, H20 has a dipole moment between the O-H bond, since the two elements have different electronegativies. And since Oxygen has a greater electronegativity than Hydrogen, the dipole moment would point towards Oxygen.

If the difference in electronegativities of the bonded elements is greater than 0.4, then the bond is polar. Similarly, if the difference is smaller than 0.4, then the bond is nonpolar.

Lourick Bustamante 1B
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Re: Dipole Moments and Polarity

Postby Lourick Bustamante 1B » Sun Dec 03, 2017 5:07 pm

How do you calculate the electronegativity for the atoms of a specific element?

Patricia Macalalag 2E
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Re: Dipole Moments and Polarity

Postby Patricia Macalalag 2E » Tue Dec 05, 2017 9:01 pm

Aren't we just supposed to analyze the electronegativity trend on the periodic table? It increases as you go left to right, and as you go up a group.

Ammar Amjad 1L
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Re: Dipole Moments and Polarity

Postby Ammar Amjad 1L » Tue Dec 05, 2017 9:20 pm

Patricia Macalalag 3G wrote:Aren't we just supposed to analyze the electronegativity trend on the periodic table? It increases as you go left to right, and as you go up a group.


Yes, electronegativity values tend to increase as you go to the right and up. I

Patricia Macalalag 2E
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Re: Dipole Moments and Polarity

Postby Patricia Macalalag 2E » Tue Dec 05, 2017 10:35 pm

It also helps to just remember Fluorine is the most electronegative, so you know elements to the upper right will be very electronegative.

Laura Riccardelli
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Re: Dipole Moments and Polarity

Postby Laura Riccardelli » Wed Dec 06, 2017 2:18 pm

If the shape of the molecule is trigonal bi-pyramidal do the dipole moments cancel because their are 5 binding sites?

Chem_Mod
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Re: Dipole Moments and Polarity

Postby Chem_Mod » Wed Dec 06, 2017 2:28 pm

The dipole moments would cancel if all the atoms attached to the central atom are the same.

Cynthia Tsang
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Re: Dipole Moments and Polarity

Postby Cynthia Tsang » Wed Dec 06, 2017 3:20 pm

In trigonal bi-pyramidal, there is no dipole moment because the five atoms around the central atom are evenly spread and symmetrical. For square pyramidal though, where there is a lone pair and 5 bonds to other atoms, this would form a dipole moment.

Radha Patel 1D
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Re: Dipole Moments and Polarity

Postby Radha Patel 1D » Wed Dec 06, 2017 4:11 pm

Electronegativity is the average of electron affinity and ionization energy which basically means that if it is hard to take an electron away from an atom and if it wants another electron to fill its shell, it is more electronegative.


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