Sapling #15

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

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Charisma Arreola 2F
Posts: 63
Joined: Wed Sep 30, 2020 9:37 pm

Sapling #15

Postby Charisma Arreola 2F » Sun Nov 29, 2020 10:05 pm

I solved for number 15, but can someone better explain the reasoning for pi bonds in a molecule and how they determine the shaping. I still do not understand the correlation. Thank you!

Sondia Luong 1C
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Joined: Wed Sep 30, 2020 10:01 pm
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Re: Sapling #15

Postby Sondia Luong 1C » Sun Nov 29, 2020 10:14 pm

Pi bonds basically happen when there are double and triple bonds. In a double bond, there is 1 pi bond and in a triple bond, there are 2 pi bonds. When it comes to the shape of the molecule, pi bonds make it so that bonded atoms can't rotate, but they still count as one region of electron density.

Hannah Alltucker 3L
Posts: 75
Joined: Wed Sep 30, 2020 9:44 pm

Re: Sapling #15

Postby Hannah Alltucker 3L » Sun Nov 29, 2020 10:22 pm

I think the important thing to note is that sigma bonds are the true determiners of a molecules shape. Pi bonds are the overlap of side to side orbitals, and is something we normally see in either double or triple bonds where you have many P orbitals (since each P has 3 orbitals in it), and sigma is an end to end overlap. While the main geometric structure is always formed by sigma bonds since they can be basically considered the skeleton of any molecule, I believe that the pi bonds mainly affect the bond length or bond angle, but don't have that large of an effect on the overall geometry since they are always paired with sigma bonds. Pi bonds also prevent a bond/atom from being able to rotate freely, which may give it a more permanent/harder to break shape

SophiaJenny3I
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Re: Sapling #15

Postby SophiaJenny3I » Sun Nov 29, 2020 10:27 pm

Hi! So a pi bond only happens in double and triple bonds. If there is a double bond, it is one sigma bond and one pi bond. If there is a triple bond, it is one sigma bond and TWO pi bonds. You can't rotate pi bonds because they are parallel side by side and that would break the bond. The sigma bond alone (single bond), on the other hand, can rotate freely. Since pi bonds cannot rotate, they are more rigid.

Charisma Arreola 2F
Posts: 63
Joined: Wed Sep 30, 2020 9:37 pm

Re: Sapling #15

Postby Charisma Arreola 2F » Mon Nov 30, 2020 10:16 pm

Thank you all!!


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