London Dispersion

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Annabella_Amato_1I
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London Dispersion

Postby Annabella_Amato_1I » Sun Nov 22, 2020 1:06 pm

Are london dispersion forces always happening between molecules? Is this even while other forces are occurring?

Brianna Martilla 1C
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Re: London Dispersion

Postby Brianna Martilla 1C » Sun Nov 22, 2020 1:08 pm

Yes, london dispersion forces are always present, but are very weak until they add up when many molecules are present.

chinmayeec 2H
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Re: London Dispersion

Postby chinmayeec 2H » Sun Nov 22, 2020 1:10 pm

London dispersion forces are always present between all molecules, and they are the only force that is present in nonpolar molecules. They become stronger in rod-shaped molecules and molecules with atoms that have high polarizability. They are also present when other interactions are occurring. For example, water experiences hydrogen bonding but also has London dispersion forces.


Hope that helps!

Giselle Granda 3F
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Re: London Dispersion

Postby Giselle Granda 3F » Sun Nov 22, 2020 1:20 pm

London dispersion forces happen in all molecules whether nonpolar or polar, and nonpolar molecules only have this force going on. Therefore, in any question that asks, just know that as a rule of thumb that all of the molecules that they ask about will automatically have LDF present, and depending on their polarity, there may be other forces present as well!

Andreas Krumbein 1L
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Re: London Dispersion

Postby Andreas Krumbein 1L » Sun Nov 22, 2020 1:31 pm

Yes, LDFs happen due to the electrons being momentarily being in a single area, causing the molecule to be momentarily polar. This happens relatively often due to the fact that an electron's position is a matter of probability (based on the uncertainty principle). So every molecule experiences LDFs at all times, and even polar molecules like water and ionic compounds experience LDFs to varying degrees.

Jonathan Banh 1G
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Re: London Dispersion

Postby Jonathan Banh 1G » Sun Nov 22, 2020 1:45 pm

London dispersion forces (LDFs) are always occurring between molecules. They rely upon the electron's typical behavior of randomness and thus are momentary differences in charge throughout the molecule that are the result of arbitrary movement. Electrons are always randomly moving, so this is why LDFs are always present, even in the presence of other forces.

Jason_Glass_2L
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Re: London Dispersion

Postby Jason_Glass_2L » Sun Nov 22, 2020 1:59 pm

Yeah, LDF happens between all molecules, but the degree of the strengths may be different depending on the size of the molecule. Larger Molecules will have larger LDF and molecules with more electrons will have stronger LDFs.

Sandy Lin 1L
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Re: London Dispersion

Postby Sandy Lin 1L » Sun Nov 22, 2020 2:34 pm

Yes LDF occurs in all molecules because the electron clouds of atoms are always changing when atoms interact.

Griffin G
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Re: London Dispersion

Postby Griffin G » Sun Nov 22, 2020 7:54 pm

Yes, london dispersion forces always exist when molecules are interacting.

Sam Wentzel 1F 14B
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Re: London Dispersion

Postby Sam Wentzel 1F 14B » Sun Nov 22, 2020 7:57 pm

LDFs are always occurring, as electrons in an atom are never stationary. The movement of electrons creates regions of differing electron density, resulting in a higher electron density field of partial negativity, and a lower electron density field of partial positivity. These partial charges induce changes in the electron densities of surrounding molecules, causing e- e- repulsion, which in turn creates a corresponding region of partial positive, and negative charge in the nearby molecule, resulting in the weak force of attraction known as LDFs.

t_rasul2I
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Re: London Dispersion

Postby t_rasul2I » Sun Nov 22, 2020 8:42 pm

London dispersion forces are always present and in every molecule including non-polar forces. There are more dispersion forces in bigger molecules because there is more surface area essentially. Therefore, bigger molecules have higher boiling points.

Anh Trinh 1J
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Re: London Dispersion

Postby Anh Trinh 1J » Sun Nov 22, 2020 8:45 pm

London Dispersion Forces are present in all molecules. The strength of it is dependent on the atoms in the molecule. Larger and heavier atoms have more electrons, and thus stronger London forces.

Carolina Gomez 2G
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Re: London Dispersion

Postby Carolina Gomez 2G » Sun Nov 22, 2020 9:07 pm

Yes, London forces occur between all molecules, they also occur while other interactions are taking place.

Hasan Mirza 3F
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Re: London Dispersion

Postby Hasan Mirza 3F » Sun Nov 22, 2020 9:19 pm

London forces are always occurring but they aren't as significant on smaller molecules, especially when compared to other intermolecular forces.

Taha 2D
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Re: London Dispersion

Postby Taha 2D » Sun Nov 22, 2020 9:20 pm

They are always present as intermolecular forces but they arent significant unless they build up.

Anthony_Sandoval_1D
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Re: London Dispersion

Postby Anthony_Sandoval_1D » Sun Nov 22, 2020 9:21 pm

To answer your question, Yes. London dispersion is occurring in all molecule interactions.

Neel Sharma 3F
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Re: London Dispersion

Postby Neel Sharma 3F » Sun Nov 22, 2020 9:46 pm

London dispersion forces or induced-dipole induced-dipole intermolecular bonds are always occurring. As the only truly non-polar bond is between two same elements, every bond has an unequal sharing of electrons based on each element's respective electronegativity. As a result, instantaneous dipoles between the positive and negative dipoles on neighboring molecules will form and weakly bond molecules together. These bonds are called London dispersion forces. They increase with greater surface area and with larger molecules. Hope this helps!

Micaela Estavillo
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Re: London Dispersion

Postby Micaela Estavillo » Sun Nov 22, 2020 9:54 pm

Yes London dipersion is alwasys present!!

Hailey Qasawadish 2J
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Re: London Dispersion

Postby Hailey Qasawadish 2J » Sun Nov 22, 2020 9:56 pm

London dispersion forces are present in all molecules as an intermolecular force!

Danielle DIS2L
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Re: London Dispersion

Postby Danielle DIS2L » Sun Nov 22, 2020 10:07 pm

Yes! LDF are always present for all molecules

Queena Chu 3E
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Re: London Dispersion

Postby Queena Chu 3E » Sun Nov 22, 2020 10:12 pm

Yes, they are always present even with other forces present!

Isabella Cortes 2H
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Re: London Dispersion

Postby Isabella Cortes 2H » Sun Nov 22, 2020 10:13 pm

london dispersion forces are always present in molecules, including when there are other forces occuring

LovepreetSran_3H
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Re: London Dispersion

Postby LovepreetSran_3H » Sun Nov 22, 2020 10:13 pm

London Dispersion Forces are always present.

Thomas Gimeno
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Re: London Dispersion

Postby Thomas Gimeno » Sun Nov 22, 2020 11:21 pm

While london dispersion forces always occur in groups of molecules, each individual molecule is not always participating in LDFs. Also LDFs can occur in one part of a molecule and not another part, all that is necessary is a sight where a difference in electron density can create a partial positive and negative charge. Even If a molecule is participating in normal dipole-dipole interactions the electrons have a chance to randomly rearrange into a different dipole which I think would then be considered a LDF. This is why polar molecules like water participate in both dipole-dipole forces and LDFs.

Susanna Givan 2B
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Re: London Dispersion

Postby Susanna Givan 2B » Sun Nov 22, 2020 11:30 pm

what determines how strong london dispersion forces are again?

Brian Nguyen 2I
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Re: London Dispersion

Postby Brian Nguyen 2I » Sun Nov 29, 2020 4:40 pm

Yes, London dispersion forces are always present. However, these forces are only significantly strong the larger the mass of the molecule.

Gabe_Ek 1G
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Re: London Dispersion

Postby Gabe_Ek 1G » Sun Nov 29, 2020 4:51 pm

Yes this is true, London dispersion forces are always present within molecules. These are usually not so strong depending if the molecular mass is relatively large or not.

Kelly Ha 1K
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Re: London Dispersion

Postby Kelly Ha 1K » Sun Nov 29, 2020 4:54 pm

Susanna Givan 1L wrote:what determines how strong london dispersion forces are again?

Generally, larger and heavier atoms have stronger dispersion forces while smaller and lighter atoms have weaker dispersion forces, which is due to the differing levels of polarizability.

Jaden Kwon 3C
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Re: London Dispersion

Postby Jaden Kwon 3C » Sun Nov 29, 2020 9:05 pm

London dispersion forces are always present between molecules as the distribution of electrons is random within atoms which can create moments of instantaneous dipoles and induced dipoles. This can occur even with other intermolecular forces present.

Mackenzie Van Val 3E
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Re: London Dispersion

Postby Mackenzie Van Val 3E » Sun Nov 29, 2020 9:38 pm

Susanna Givan 1L wrote:what determines how strong london dispersion forces are again?


Large, heavy atoms have stronger London Dispersion forces than smaller, lighter atoms because they are more polarizable and have more electrons. On a related note, the larger the surface area of an atom, the stronger its London Dispersion Forces will be.

Jeremy Wei 2C
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Re: London Dispersion

Postby Jeremy Wei 2C » Sun Dec 06, 2020 9:26 pm

Hi London Dispersion forces exist in all molecules! However, molecules bigger in size will have stronger London dispersion forces compared to a smaller molecule.

Lauren Strickland 1B
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Re: London Dispersion

Postby Lauren Strickland 1B » Sun Dec 06, 2020 9:36 pm

Yes they are always present in molecules.

Bai Rong Lin 2K
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Re: London Dispersion

Postby Bai Rong Lin 2K » Sun Dec 06, 2020 10:15 pm

chinmayeec 3L wrote:London dispersion forces are always present between all molecules, and they are the only force that is present in nonpolar molecules. They become stronger in rod-shaped molecules and molecules with atoms that have high polarizability. They are also present when other interactions are occurring. For example, water experiences hydrogen bonding but also has London dispersion forces.


Hope that helps!

This is actually very helpful! It helps explain a lot of the question I had on the London dispersion force

DPatel_2L
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Re: London Dispersion

Postby DPatel_2L » Fri Dec 11, 2020 7:48 pm

Yes, they are always present.


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