sigma or pi?


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Giovanni Anguiano-Gutierrez 3L
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sigma or pi?

Postby Giovanni Anguiano-Gutierrez 3L » Sun Nov 24, 2019 9:25 pm

For hybridized orbitals, how do we know if a bond is sigma or pi just based on lewis structures? Are all hybrid orbitals sigma bonds?

Brianna Becerra 1B
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Joined: Fri Aug 02, 2019 12:16 am

Re: sigma or pi?

Postby Brianna Becerra 1B » Sun Nov 24, 2019 9:27 pm

If there is a single bond, it is sigma, if it is a double, it is sigma and pi and if there is a triple bond then it is considered one sigma two pi.
Last edited by Brianna Becerra 1B on Sun Nov 24, 2019 9:31 pm, edited 1 time in total.

gferg21
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Re: sigma or pi?

Postby gferg21 » Sun Nov 24, 2019 9:28 pm

a sigma bond is the "first bond" that an atom makes to another, whereas pi bonds are the "second" or "third." If there is only a single bond then that is a sigma bond but if there is more than one there is a pi bond.

Jordan Ziegler 2J
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Re: sigma or pi?

Postby Jordan Ziegler 2J » Sun Nov 24, 2019 9:29 pm

Just to clarify: a single bond is one sigma, a double bond is a sigma and a pi, and a triple bond is a sigma and two pi bonds.

SVajragiri_1C
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Re: sigma or pi?

Postby SVajragiri_1C » Sun Nov 24, 2019 9:30 pm

When you draw the Lewis structure, a signle bond has one sigma bond, a double bond has one sigma and one pi bond, and a triple bond has one sigma and two pi bonds.

TanveerDhaliwal3G
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Re: sigma or pi?

Postby TanveerDhaliwal3G » Sun Nov 24, 2019 10:25 pm

All single bonds are sigma bonds. A double bonds has one sigma bond and one pi bond and a triple bond has one sigma bond and two pi bonds.

Julieta Serobyan4D
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Re: sigma or pi?

Postby Julieta Serobyan4D » Sun Nov 24, 2019 10:26 pm

Giovanni Anguiano-Gutierrez 3L wrote:For hybridized orbitals, how do we know if a bond is sigma or pi just based on lewis structures? Are all hybrid orbitals sigma bonds?

A single bond has one sigma , then afterwards double bond has one sigma and one pi and etc.

RasikaObla_4I
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Re: sigma or pi?

Postby RasikaObla_4I » Sun Nov 24, 2019 10:27 pm

A single bond is a sigma bond and any additional bonds after that connecting the same elements are pi bonds.

504939134
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Joined: Wed Sep 18, 2019 12:21 am

Re: sigma or pi?

Postby 504939134 » Sun Nov 24, 2019 10:39 pm

Whenever you see a single bond know that it is sigma. When you see a double or triple bond one will be sigma and the other two will be pi bonds. Sigma bonds are single covalent bonds.

705379941
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Joined: Fri Aug 30, 2019 12:16 am

Re: sigma or pi?

Postby 705379941 » Sun Nov 24, 2019 10:41 pm

single bonds are always signa, while double bonds & triple bonds start with one signa & then the rest are pi .

Sofia Barker 2C
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Re: sigma or pi?

Postby Sofia Barker 2C » Sun Nov 24, 2019 11:27 pm

Remember that the first bond formed is a sigma bond and every bond formed thereafter between the same pair of atoms is a pi bond.

pJimenez3F
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Re: sigma or pi?

Postby pJimenez3F » Sun Nov 24, 2019 11:34 pm

a single bond, is sigma, if it is a double bond, it is sigma and pi and if there is a triple bond then it is one sigma two pi.

kendal mccarthy
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Re: sigma or pi?

Postby kendal mccarthy » Sun Nov 24, 2019 11:49 pm

A sigma bond is any single bond in a molecule, including 1 out of the 2 bonds in a double bond and 1 out of the 3 bonds in triple bonds. A pi bond is any 2nd or 3rd bond in a double or triple bond.

Kelsey Ash 1D
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Re: sigma or pi?

Postby Kelsey Ash 1D » Mon Nov 25, 2019 1:16 pm

Since sigma bonds always form first if there is a single bond then it is a sigma bond, if there is a double bond then there is one single bond and one pi bond present, and if there is a triple bond then there is still only 1 sigma bond but 2 pi bonds.

Mandeep Garcha 2H
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Re: sigma or pi?

Postby Mandeep Garcha 2H » Mon Nov 25, 2019 11:43 pm

single bond: 1 sigma, o pi
double bond: 1 sigma, 1 pi
triple bond: 1 sigma, 2 pi

Shrayes Raman
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Re: sigma or pi?

Postby Shrayes Raman » Wed Nov 27, 2019 2:29 am

If a Lewis structure includes a double bond it will have a pi bond in the double bond

Jialun Chen 4F
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Re: sigma or pi?

Postby Jialun Chen 4F » Wed Nov 27, 2019 3:29 am

Just memorize:
single bond: one sigma bond
double bond: one sigma bond, one pi bond
triple bond: one sigma bond, 2 pi bonds

Esha Chawla 2E
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Joined: Thu Jul 25, 2019 12:17 am

Re: sigma or pi?

Postby Esha Chawla 2E » Wed Nov 27, 2019 2:26 pm

Giovanni Anguiano-Gutierrez 3L wrote:For hybridized orbitals, how do we know if a bond is sigma or pi just based on lewis structures? Are all hybrid orbitals sigma bonds?


Everyone in the comments above has already mentioned that the first bond is a sigma bond and that subsequent bonds are pi bonds. To add onto that, know that a single, sigma bond is extremely weak and flexible. Thus, if two atoms are connected by sigma bonds, they are extremely flexible and capable of rotating in different planes. On the other hand, once pi bonds are added (1 or 2 pi bonds depending on if its a double or triple bond), the molecule becomes a lot stiffer and incapable of rotating.

Matthew ILG 1L
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Re: sigma or pi?

Postby Matthew ILG 1L » Wed Nov 27, 2019 4:35 pm

The way i remember is: Sigma=Single. The double S helps me out. Also sigma bonds are every bond in a structure.

emwoodc
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Re: sigma or pi?

Postby emwoodc » Fri Nov 29, 2019 9:16 pm

you count the number of bonds there are. for example, a single bond is a sigma bond, a double bond is sigma and pi, and a triple bond is sigma and two pi.

ranqiao1e
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Re: sigma or pi?

Postby ranqiao1e » Fri Nov 29, 2019 9:27 pm

If it’s a single bond, then the bond is sigma. If it’s a double bond, then the bond is pi.


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