Sigma and Pi bonds

(Polar molecules, Non-polar molecules, etc.)

Moderators: Chem_Mod, Chem_Admin

taiyeojeikere-3C
Posts: 30
Joined: Fri Sep 28, 2018 12:26 am

Sigma and Pi bonds

Postby taiyeojeikere-3C » Sat Nov 24, 2018 9:12 pm

What is the difference between sigma and pi bonds and what does it mean by component orbitals?

Chloe Thorpe 1J
Posts: 77
Joined: Fri Sep 28, 2018 12:16 am

Re: Sigma and Pi bonds

Postby Chloe Thorpe 1J » Sat Nov 24, 2018 10:00 pm

In short, the difference is that sigma bonds overlap end-to-end and are the strongest covalent bonds, while pi bonds overlap side-by-side. I believe "component orbital" refers to the orbitals that sort of make up the hybrid orbital. For example, in 2sp, the component orbitals would be 2s, 2p. Not 100% certain though.

yaosamantha4F
Posts: 31
Joined: Fri Sep 28, 2018 12:29 am

Re: Sigma and Pi bonds

Postby yaosamantha4F » Sat Nov 24, 2018 11:01 pm

Adding on, because sigma bonds overlap end-to-end, they allow bound atoms to rotate, while pi bonds, which overlap side-to-side, do not allow bound atoms to rotate. Sigma bonds are also formed between atoms, while pi bonds are formed above/under/beside sigma bonds.

taywebb
Posts: 60
Joined: Fri Sep 28, 2018 12:15 am

Re: Sigma and Pi bonds

Postby taywebb » Sun Nov 25, 2018 2:40 pm

When determining the number of sigma and pi bonds in a molecule, do you have to put them only for the most common resonance structure? (Referring to homework problem 2F #3 for the SO2 lewis structures)

annabel 2A
Posts: 67
Joined: Fri Sep 28, 2018 12:18 am

Re: Sigma and Pi bonds

Postby annabel 2A » Sun Nov 25, 2018 2:52 pm

If there is a double bond will there always be 1 sigma and 1 pi bond?

Keshav Bhatnagar 1H
Posts: 32
Joined: Fri Sep 28, 2018 12:17 am

Re: Sigma and Pi bonds

Postby Keshav Bhatnagar 1H » Sun Nov 25, 2018 3:07 pm

annabel 1F wrote:If there is a double bond will there always be 1 sigma and 1 pi bond?


Yes, the first bond is always a sigma bond, but bonds after that are pi bonds.

Anna O 2C
Posts: 98
Joined: Fri Sep 28, 2018 12:19 am

Re: Sigma and Pi bonds

Postby Anna O 2C » Sun Nov 25, 2018 5:54 pm

Pi bonds result because you can't have 2 sigma bonds in a double bond. Sigma bonds are the shortest and connect the two atoms most directly. Any other bond that occurs will have to arch around the existing bond to reach the other atom and thus become a pi bond. Every bond formed after the initial single sigma bond has the potential to be a pi bond but not a sigma bond.


Return to “Determining Molecular Shape (VSEPR)”

Who is online

Users browsing this forum: No registered users and 1 guest