pi-bonds

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

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akroberts
Posts: 24
Joined: Fri Sep 28, 2018 12:16 am

pi-bonds

Postby akroberts » Sun Nov 25, 2018 11:05 pm

How can we recognize when a pi-bond is formed?

rikolivares
Posts: 24
Joined: Fri Sep 28, 2018 12:23 am

Re: pi-bonds

Postby rikolivares » Sun Nov 25, 2018 11:20 pm

When there is more than a single bond.

305117729
Posts: 30
Joined: Fri Sep 28, 2018 12:16 am

Re: pi-bonds

Postby 305117729 » Sun Nov 25, 2018 11:40 pm

pi bond is formed by overlapping between p orbitals, or say parallel interactions between p orbitals. So it will only be formed when two atoms with their p orbitals overlapping, and it means that only when a double or triple bond formed, pi bonds will be formed, since the s orbitals form the single bond, namely sigma bond.

duverge_maciel
Posts: 21
Joined: Fri Sep 28, 2018 12:16 am

Re: pi-bonds

Postby duverge_maciel » Sun Nov 25, 2018 11:54 pm

Why do pi bonds not allow bound atoms to rotate?

Angel Chen 2k
Posts: 59
Joined: Fri Sep 28, 2018 12:20 am

Re: pi-bonds

Postby Angel Chen 2k » Sun Nov 25, 2018 11:58 pm

Basically, a pair of double bonds consists of one sigma bond and a pi bond. Triples bonds contain one sigma bond and two pi bonds.

Hope this helps!

Sydney Aurelio_Dis4B
Posts: 30
Joined: Fri Sep 28, 2018 12:28 am

Re: pi-bonds

Postby Sydney Aurelio_Dis4B » Mon Nov 26, 2018 12:06 am

duverge_maciel wrote:Why do pi bonds not allow bound atoms to rotate?

Pi bonds do not allow bound atoms to rotate because rotating the atoms weakens the pi bonds. Pi bonds are the strongest when the p orbitals between atoms are parallel.

Josceline 3J
Posts: 33
Joined: Fri Sep 28, 2018 12:21 am

Re: pi-bonds

Postby Josceline 3J » Mon Nov 26, 2018 1:13 am

You could think of it as the second bond that is made. The sigma is the first bond (electrons are taken from the center, C--O ). The pi is formed by taking electrons from around the atom to create bonds. I'm not sure if it makes sense unless you see it, at least that's how they showed me.

505194972 3k
Posts: 27
Joined: Fri Sep 28, 2018 12:25 am

Re: pi-bonds

Postby 505194972 3k » Mon Nov 26, 2018 1:56 am

duverge_maciel wrote:Why do pi bonds not allow bound atoms to rotate?

Professor Lavelle gave a very good example in lecture when he held two pencils parallel between his two hands and when he twisted them the pencils fell. if the atom rotated the bonds would break. I believe the pi bond stabilizes the molecule.


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