London Dispersion Forces

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Emma Healy 2J
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London Dispersion Forces

Postby Emma Healy 2J » Sun Nov 15, 2020 11:59 pm

Why do all molecules experience London Dispersion Forces?

Ximeng Guo 2K
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Re: London Dispersion Forces

Postby Ximeng Guo 2K » Mon Nov 16, 2020 12:04 am

Atoms in molecule have electrons and positive nuclei, so there will always be some random fluctuation of charges (induced dipole) when molecules come closer and interact with each other. It thus creates London Dispersion Forces.

Katie Phan 1K
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Re: London Dispersion Forces

Postby Katie Phan 1K » Mon Nov 16, 2020 12:13 am

They all have dispersion forces because at some moment in time, nonpolar molecules can have temporary dipoles.

Gabriel Nitro 1E
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Re: London Dispersion Forces

Postby Gabriel Nitro 1E » Mon Nov 16, 2020 7:41 am

Hi,

It is important to note that London Dispersion Forces arise from electrons. As the delocalized electrons of a given particle are moving around at any given moment in time, if you were to take a snapshot over a given interval you would see that at some point the electrons would be dispersed in such a way a temporary dipole (i.e. a temporary separation of charge) is formed. And, considering electrons constitute all molecules/ions, LDFs are present in all of them.

Hope this helps! :)

sophie esherick 3H
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Re: London Dispersion Forces

Postby sophie esherick 3H » Mon Nov 16, 2020 8:49 am

Hi!

LDF or Induced Dipole- Induced Dipole forces are always present and attractive because all compounds have electrons. Electron density can fluctuate so as they interact, there are brief moments when the electron repel one another so one end becomes slightly positive and the other becomes slightly negative. This electron density will influenced neighboring molecules once they get closer to one another producing a temporary dipole moments. This happens because electrons are always going to fluctuate in such a way that there are attractive/favorable interactions. The strength of LDF depends on the distance between atoms/molecules and their polarizability. Increasing the molar mass/size therefore results in stronger attractive forces.

Hope this helps!

Mia Meza
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Re: London Dispersion Forces

Postby Mia Meza » Mon Nov 16, 2020 7:27 pm

Could someone explain why CH3CHO shows london dispersion interactions.

KhanTran3K
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Re: London Dispersion Forces

Postby KhanTran3K » Mon Nov 16, 2020 7:38 pm

Hey!
All molecules exhibit london dispersion forces, but correct me if I am wrong, I believe that CH3CHO would also exhibit dipole dipole interactions since it is a polar molecule. It would not exhibit hydrogen bonds since none of the Hydrogens are bonded to a highly electronegative molecule, N, O, or F. Hope that helps!

Vanshika Bhushan 1A
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Re: London Dispersion Forces

Postby Vanshika Bhushan 1A » Tue Nov 17, 2020 12:54 pm

All molecules experience London dispersion forces because each molecule have moments where their electrons move to one side of the atom. The atom becomes slightly negative and slightly positive on either sides, which attracts another atom.

kristinalaudis3e
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Re: London Dispersion Forces

Postby kristinalaudis3e » Sun Dec 06, 2020 11:28 pm

London dispersion forces happen in all molecules because electrons are constantly moving around the nucleus and when electrons randomly become closer to each other, they create temporary dipoles which is a form of attraction.


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