Resonance

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Mahnoor_Wani_1I
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Resonance

Postby Mahnoor_Wani_1I » Sat Nov 14, 2020 7:40 pm

How does resonance lowers energy and make molecules stable?
Last edited by Mahnoor_Wani_1I on Sat Nov 14, 2020 10:30 pm, edited 1 time in total.

Kelly Yun 2I
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Re: Resonance

Postby Kelly Yun 2I » Sat Nov 14, 2020 7:43 pm

Sometimes there can be multiple structures that are favored so we come up with resonance structures. In these structures, electrons are delocalized and occupy a larger volume, which lowers the energy of a molecule and stabilizes it.

Karen Elrayes 1L
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Re: Resonance

Postby Karen Elrayes 1L » Sat Nov 14, 2020 9:16 pm

What is x-ray diffraction again?

Karen Elrayes 1L
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Re: Resonance

Postby Karen Elrayes 1L » Sat Nov 14, 2020 9:38 pm

also why are resonance structures more stable?

Astha Sahoo 3I
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Re: Resonance

Postby Astha Sahoo 3I » Sat Nov 14, 2020 10:20 pm

I believe they are more stable because the electrons are moving around more, stabilizing charge, and thus there is less energy used to stabilize charge and bond the atoms.

Karen Elrayes 1L
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Re: Resonance

Postby Karen Elrayes 1L » Sat Nov 14, 2020 11:35 pm

Ahh yes that makes a lot more sense thank you

Sheryl Ocampo 1D
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Re: Resonance

Postby Sheryl Ocampo 1D » Sun Nov 15, 2020 12:23 am

Resonance structures are multiple structures of the same molecule. Some of these resonance structures have a lower formal charge, making them more favorable and more stable

Arnav Saud 2C
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Re: Resonance

Postby Arnav Saud 2C » Sun Nov 15, 2020 12:47 am

Some resonance structures are more stable because their formal charges are minimized. The more charges in the structure that equal zero, the more stable it is.
Additionally, the placement of negative and positive charges also differs between different resonance structures.
Negative formal charges on more electronegative charges makes the structure more stable as well.

MMorcus2E
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Re: Resonance

Postby MMorcus2E » Sun Nov 15, 2020 12:55 am

Resonance structures are multiple Lewis structures for the same molecule. They account for delocalized electrons' ability to move around within a molecule. Resonance structures are related to stability because different structures lead to different formal charges on different atoms, which affects the molecule's stability overall.

Colin Squire 3B
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Re: Resonance

Postby Colin Squire 3B » Sun Nov 15, 2020 1:54 am

By adding different bonds to the same Lewis Structure, without going over the total number of electrons, you can change the formal charge of any of the molecules (usually as close to zero as you can get) to get them more stable. Essentially, by finding the different structures of the same molecule, you can find out which is the most stable.

Gian Boco 2G
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Re: Resonance

Postby Gian Boco 2G » Sun Nov 15, 2020 4:45 am

Resonance structures are just different Lewis structures of the same molecule. The most stable resonance structures would have the least number of atoms with a formal charge and most especially a sum closest to 0 for formal charges of the whole molecule.

Keshav Patel 14B 2B
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Re: Resonance

Postby Keshav Patel 14B 2B » Sun Nov 15, 2020 11:20 am

The reason why resonance lowers energy is due to the double bond that there is. Because of a bond having resonance, all the bond lengths become shorter due to partial bond lengths. Basically, now all the bonds are shorter because of the resonance.

Gerardo Ortega 2F
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Re: Resonance

Postby Gerardo Ortega 2F » Sun Nov 15, 2020 11:24 am

Adding to the previous comments, an optimal resonance structure tends to have a negative charge on the most electronegative atom in the molecule.

Simi Kapila_3E
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Re: Resonance

Postby Simi Kapila_3E » Sun Nov 15, 2020 11:35 am

Resonance shows that there are multiple structures for a single molecule. However, the way we draw resonance structures isn't completely accurate, and the actual structure is usually a blend of the resonance structures, which provides the molecule with more stability.

Kat Stahl 2K
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Re: Resonance

Postby Kat Stahl 2K » Sun Nov 15, 2020 11:50 am

Keshav Patel 14A 3B wrote:The reason why resonance lowers energy is due to the double bond that there is. Because of a bond having resonance, all the bond lengths become shorter due to partial bond lengths. Basically, now all the bonds are shorter because of the resonance.

My TA explained it really well in my last discussion section. He used the example CO3^2-. This compound has 3 resonance structures and in each one, one of the oxygens is double bonded to the carbon. What this means is that that extra bond is being shared by all of the oxygen carbon bonds. So what that means is that each oxygen carbon has a 1 & 1/3 bond (1/3 because that one extra bond is split between the three oxygens). Hope this made sense.

Zainab Jamali 1H
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Re: Resonance

Postby Zainab Jamali 1H » Sun Nov 15, 2020 12:16 pm

Resonance structures have delocalized electrons which are very stable and contribute to the overall stability of the molecule.

Karina Grover 1A
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Re: Resonance

Postby Karina Grover 1A » Sun Nov 15, 2020 12:19 pm

In resonance structures, electrons are delocalized, meaning that they can move around within different bonds and they can occupy larger volumes. The most stable structure has the smallest quantity/amount of formal charges.

Haochen He 3L
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Re: Resonance

Postby Haochen He 3L » Sun Nov 15, 2020 6:46 pm

I think the reason is that in resonance structures, electrons move around more (delocalized electrons), which requires less energy to stablize the structure

Lauren Sarigumba 1K
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Re: Resonance

Postby Lauren Sarigumba 1K » Sun Nov 15, 2020 6:53 pm

The most stable resonance structure minimizes formal charges, meaning that it has the fewest number of and smallest magnitude of formal charges. And the negative formal charges are on the more electronegative atoms. Resonance structures are multiple Lewis structures that collectively represent a molecule and they all have the same molecular formulas, the same atom connectivities, the same overall charges, and the same number of electrons.

Jessica Hu 3L
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Re: Resonance

Postby Jessica Hu 3L » Sun Nov 15, 2020 7:03 pm

I think also a good way to think about it is as if the energy from all the electrons are distributed between more atoms, which lowers the energy magnitude of the entire molecule. it's also important to remember that resonance structures represent a singular molecule.


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