Dipole Moments and Polarity
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Dipole Moments and Polarity
Can someone please clarify how to find/determine the dipole of a molecule and how you can find polarity with that?
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Re: Dipole Moments and Polarity
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.
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.
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Re: Dipole Moments and Polarity
How do you calculate the electronegativity for the atoms of a specific element?
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Re: Dipole Moments and Polarity
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.
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Re: Dipole Moments and Polarity
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
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Re: Dipole Moments and Polarity
It also helps to just remember Fluorine is the most electronegative, so you know elements to the upper right will be very electronegative.
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Re: Dipole Moments and Polarity
If the shape of the molecule is trigonal bi-pyramidal do the dipole moments cancel because their are 5 binding sites?
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Re: Dipole Moments and Polarity
The dipole moments would cancel if all the atoms attached to the central atom are the same.
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Re: Dipole Moments and Polarity
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.
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Re: Dipole Moments and Polarity
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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