delocalized pi bonds


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Annabella_Amato_1I
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delocalized pi bonds

Postby Annabella_Amato_1I » Sun Nov 29, 2020 1:25 pm

How can you tell if there is a delocalized pi bond by just looking at the molecular formula?

Joseph Hsing 2C
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Re: delocalized pi bonds

Postby Joseph Hsing 2C » Sun Nov 29, 2020 1:28 pm

If you can imagine the Lewis structure in your head from the molecular formula, then you can check for resonance and as a result delocalized pi bonds. I would recommend just drawing out the different structures just to be safe though and more practice.

Rylee Mangan 1K
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Re: delocalized pi bonds

Postby Rylee Mangan 1K » Sun Nov 29, 2020 1:29 pm

If you know the molecule has resonance (and double bonds) then it is likely delocalized pi bonds are present. Visualizing these structures for homework is fine but to ensure correctness you should draw them out.

605291562
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Re: delocalized pi bonds

Postby 605291562 » Sun Nov 29, 2020 3:17 pm

When a molecule has resonance the electrons are delocalized because there most stable state is somewhere between the lewis structures we can draw and most likely double bonds are present, these structures would have delocalized pi bonds.

Sophia Kalanski 1A
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Re: delocalized pi bonds

Postby Sophia Kalanski 1A » Sun Nov 29, 2020 3:26 pm

delocalized pi bonds occur when there are resonance structures. If a pi bond can exist in a different region, then it is delocalized.

Gigi Elizarraras 2C
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Re: delocalized pi bonds

Postby Gigi Elizarraras 2C » Sun Nov 29, 2020 3:29 pm

I would definitely recommend drawing out the lewis structure to see if there are possible resonance structures. If there are then you will have delocalized pi bonds. Better to be safe than sorry:)

Tatyana Bonnet 2H
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Re: delocalized pi bonds

Postby Tatyana Bonnet 2H » Sun Nov 29, 2020 3:47 pm

As others have said drawing out the lewis structure and determining if it has resonance will help to determine if it has delocalized pi bonds. HCN for example when drawn out shows C and N having a triple bond indicating it has 2 pi bonds. However HCN does not have resonance so the pi bonds are not delocalized.

Ethan Goode 2H
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Re: delocalized pi bonds

Postby Ethan Goode 2H » Sun Nov 29, 2020 3:50 pm

I am confused as to what a delocalized pi bond is. Does that just mean there is resonance?

Tobie Jessup 2E
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Re: delocalized pi bonds

Postby Tobie Jessup 2E » Sun Nov 29, 2020 4:00 pm

Joseph Hsing 3H wrote:If you can imagine the Lewis structure in your head from the molecular formula, then you can check for resonance and as a result delocalized pi bonds. I would recommend just drawing out the different structures just to be safe though and more practice.


This was helpful thank you!

105405231
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Re: delocalized pi bonds

Postby 105405231 » Sun Nov 29, 2020 4:09 pm

Hi Ethan,

A delocalized pi bond does infer that there is resonance in a molecule's Lewis Structure. Resonance is simply the method of describing delocalized electrons in a molecule, where the molecule's Lewis Structure can be represented by several different structures.

Brandon McClelland3L
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Re: delocalized pi bonds

Postby Brandon McClelland3L » Sun Nov 29, 2020 7:53 pm

In a molecule where there is a pi bond, the pi bond is delocalized if it is in a different place in a resonance structure.

Keshav Patel 14B 2B
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Re: delocalized pi bonds

Postby Keshav Patel 14B 2B » Sun Nov 29, 2020 8:41 pm

Delocalized pi bonds always happen with resonance of atoms that have multiple bonds, typically double bonds. They are also in a circular pattern such as a hexagonal shape, so if you have a carbon chain with the same amount of hydrogen chances are you have delocalized pi bonds.

LeanneBagood_2F
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Re: delocalized pi bonds

Postby LeanneBagood_2F » Sun Nov 29, 2020 8:48 pm

just to clarify, the best way to determine if there is a delocalized pi bond is to first draw a lewis structure and then see if there is resonance? if there is resonance then there is a delocalized pi bond, but if not, there is none?

can someone briefly explain how resonance connected to a delocalized pi bond please? im still a bit confused

Jerry_T
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Re: delocalized pi bonds

Postby Jerry_T » Sun Nov 29, 2020 8:57 pm

Drawing the Lewis structure can help you identify whether a compound has delocalized pi bonds. For a compound that has a resonance structure(s) containing pi bonds (double and triple bonds), then it is said to have delocalized pi bonds because the pi orbitals extend over more than two atoms. An example would be benzene, which is commonly drawn with a ring to represent the delocalized pi bonds.

Chenning Yang Dis3l
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Re: delocalized pi bonds

Postby Chenning Yang Dis3l » Sun Nov 29, 2020 9:02 pm

Thank you for the post!

Giselle_zamora_1L
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Re: delocalized pi bonds

Postby Giselle_zamora_1L » Sun Nov 29, 2020 11:11 pm

Can someone explains what delocalized pi bonds are and how they differ from delocalized electron bonds ?


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