Bond Lengths  [ENDORSED]

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Sara Varadharajulu
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Bond Lengths

Postby Sara Varadharajulu » Sat Nov 04, 2017 8:50 pm

Why are multiple bonds shorter than a single bond between the same two elements?

Christian Fulinara 3H
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Re: Bond Lengths

Postby Christian Fulinara 3H » Sat Nov 04, 2017 8:58 pm

"Multiple bonds are shorter than single bonds between the same two elements, because the additional bonding electrons attract the nuclei more strongly and pull the atoms closer together" (96). So basically, the more bonds there are, the shorter the bonds are.

Nhan Nguyen 2F
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Re: Bond Lengths

Postby Nhan Nguyen 2F » Sat Nov 04, 2017 11:21 pm

To elaborate on Christian's post,
Triple bonds are strongest, followed by doubles and single bonds. Bond length decreases as bond strength increases. Shorter bond lengths do not need to be long because attractions pull electrons closer.

Guangyu Li 2J
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Re: Bond Lengths

Postby Guangyu Li 2J » Sun Nov 05, 2017 12:04 am

A single bond only has a pi bond. A double bond contains a pi bond and a sigma bond.

Whereas a pi bond is stronger and difficult to break, a sigma bond requires more energy to sustain the interaction between atoms. As a result, in order to form a sigma bond, two atoms have to be closer to each other. Therefore, a double bond is shorter than a single bond.

Hope this helps and have a nice weekend.

Michelle Lee 2E
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Re: Bond Lengths

Postby Michelle Lee 2E » Sun Nov 05, 2017 4:36 pm

In response to Guangyu Li's post, what would be the bond for a triple bond then? And is there any specific reason for the names, i.e. sigma and pi? We didn't learn this is lecture.

Jasmine Botello 2F
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Re: Bond Lengths

Postby Jasmine Botello 2F » Tue Nov 07, 2017 4:35 pm

are we supposed to know about pi bonds for the midterm?? I do not remember going over them in class.

Natalie LeRaybaud 1G
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Re: Bond Lengths

Postby Natalie LeRaybaud 1G » Tue Nov 07, 2017 7:42 pm

No I don't think that you will have to know pi bonds for the midterm.

Kai_Chiu 1F
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Re: Bond Lengths

Postby Kai_Chiu 1F » Sat Nov 11, 2017 4:05 pm

@Michelle Lee_3C, in a triple bond, there are two pi bonds and one sigma bond.

Chem_Mod
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Re: Bond Lengths  [ENDORSED]

Postby Chem_Mod » Sat Nov 11, 2017 4:46 pm

These are all correct. Remember, if something is not discussed in lecture, you are not responsible for knowing it! It's just extra information for the curious minds. :)


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