Last Bullet of Outline 4

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Vivian Hoang 1H
Posts: 64
Joined: Wed Sep 30, 2020 10:09 pm

Last Bullet of Outline 4

Postby Vivian Hoang 1H » Sat Nov 28, 2020 9:44 pm

Hi! Reviewing the bullets of outline 4..

Please tell me everything you know for describing the structure of a molecule, cation, or anion in terms of hybrid orbitals and sigma and
pi bonds!

Keerthana Sundar 1K
Posts: 61
Joined: Wed Sep 30, 2020 9:52 pm

Re: Last Bullet of Outline 4

Postby Keerthana Sundar 1K » Sat Nov 28, 2020 10:18 pm

Please tell me everything you know for describing the structure of a molecule, cation, or anion in terms of hybrid orbitals and sigma and
pi bonds!


- To describe the structure of a molecule, cation, or anion, you will need to know the amount of lone pairs on the central atom and the amount of bonds on the central atom. This will help you use the VSEPR theory to determine a shape.
- To determine the shape with a hybrid orbital, you will need to determine how many areas of electron density are there, and based on that chose the right hybrid orbital (ex. with 4 regions, you would do sp3, 5 regions sp3d, etc)
- Every bond is a sigma bond, unless it has double bonds, triple bonds, or more, in which case the first bond is a sigma bond and the second, third, etc bond is pi bond I believe (correct me if I'm wrong).

This is all I can think of at the moment, so if anyone has anything to add, feel free!

Rohit Srinivas 2D
Posts: 63
Joined: Wed Sep 30, 2020 9:52 pm

Re: Last Bullet of Outline 4

Postby Rohit Srinivas 2D » Sun Nov 29, 2020 6:42 pm

Keerthana Sundar 1E wrote:
Please tell me everything you know for describing the structure of a molecule, cation, or anion in terms of hybrid orbitals and sigma and
pi bonds!


- To describe the structure of a molecule, cation, or anion, you will need to know the amount of lone pairs on the central atom and the amount of bonds on the central atom. This will help you use the VSEPR theory to determine a shape.
- To determine the shape with a hybrid orbital, you will need to determine how many areas of electron density are there, and based on that chose the right hybrid orbital (ex. with 4 regions, you would do sp3, 5 regions sp3d, etc)
- Every bond is a sigma bond, unless it has double bonds, triple bonds, or more, in which case the first bond is a sigma bond and the second, third, etc bond is pi bond I believe (correct me if I'm wrong).

This is all I can think of at the moment, so if anyone has anything to add, feel free!


Additionally, the angles at which pi and sigma bonds are formed at could be useful. Pi bonds are perpendicular when they occur with the p shell. They also lock rotation while sigma bonds do not.

Vivian Hoang 1H
Posts: 64
Joined: Wed Sep 30, 2020 10:09 pm

Re: Last Bullet of Outline 4

Postby Vivian Hoang 1H » Fri Dec 04, 2020 11:50 am

Rohit Srinivas 1C wrote:
Keerthana Sundar 1E wrote:
Please tell me everything you know for describing the structure of a molecule, cation, or anion in terms of hybrid orbitals and sigma and
pi bonds!


- To describe the structure of a molecule, cation, or anion, you will need to know the amount of lone pairs on the central atom and the amount of bonds on the central atom. This will help you use the VSEPR theory to determine a shape.
- To determine the shape with a hybrid orbital, you will need to determine how many areas of electron density are there, and based on that chose the right hybrid orbital (ex. with 4 regions, you would do sp3, 5 regions sp3d, etc)
- Every bond is a sigma bond, unless it has double bonds, triple bonds, or more, in which case the first bond is a sigma bond and the second, third, etc bond is pi bond I believe (correct me if I'm wrong).

This is all I can think of at the moment, so if anyone has anything to add, feel free!


Additionally, the angles at which pi and sigma bonds are formed at could be useful. Pi bonds are perpendicular when they occur with the p shell. They also lock rotation while sigma bonds do not.


Thanks for the replies! This is very helpful for studying for the final. Good luck!


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