Linear VSEPR model

[Marni Kahn 1A]

I know that when the central atom has only two bonding pairs as far as possible, forming an 180 degree angle, it is considered to be a linear shape, but what if the central atom has lone pairs in addition to the two bonds?

[Kate Osborne 1H]

If the central atom has either zero or three non bonding electron domains in addition to the two bonding it is linear but any other number would be some other shape.

[Katherine Chhen 3I]

So the number of lone pairs can also determine the molecular shape of a molecule?

[Kate Osborne 1H]

In lecture Dr. Lavelle only went over examples where there are no lone pairs, but yes lone pairs do influence shape and I believe we will learn about it on Friday during lecture.

[SGonzales_3L]

If the central atom has either zero or three non bonding electron domains in addition to the two bonding it is linear but any other number would be some other shape.

Yes, we haven't learned it yet, but lone pairs also influence the shape of molecules due to electron-electron repulsions. In the book, it is discussed in section 2E.2, so I think we'll learn it very soon.

[Diana Chavez-Carrillo 2L]

So the number of lone pairs can also determine the molecular shape of a molecule?

Yes, lone pairs can influence the molecular shape of a molecule but as mentioned by the previous responses we have not gone over it yet. However, to have an idea of some examples I provided an image below that shows you some shapes with lone pairs. I think it would be good to just see them and have an idea of how they look so when Lavelle does go over it you have some idea of how the shapes with lone pairs look like. Hope that helps :)

[Callum Guo 1H]

Lone pairs on the central atom adds a domain onto the central atom so it would not be linear. For example if you had H2O, the electron geometry would be tetrahedral because of 2 O-H bonds and 2 lone pairs.

[KBELTRAMI_1E]

I know that when the central atom has only two bonding pairs as far as possible, forming an 180 degree angle, it is considered to be a linear shape, but what if the central atom has lone pairs in addition to the two bonds?

I was also confused about this in the homework, I think it depends on the angle? not sure

[KBELTRAMI_1E]

So the number of lone pairs can also determine the molecular shape of a molecule?

Yes, lone pairs can influence the molecular shape of a molecule but as mentioned by the previous responses we have not gone over it yet. However, to have an idea of some examples I provided an image below that shows you some shapes with lone pairs. I think it would be good to just see them and have an idea of how they look so when Lavelle does go over it you have some idea of how the shapes with lone pairs look like. Hope that helps :)

wait so for the photo what would 1 lone pair look like for the first row

[Minh Ngo 4G]

The lone pair does affect the shape because of the repulsion so it pushes the two bonds downward more. The shape wouldn’t be linear since the angle is no longer 180.

[Diana Chavez-Carrillo 2L]

So the number of lone pairs can also determine the molecular shape of a molecule?

Yes, lone pairs can influence the molecular shape of a molecule but as mentioned by the previous responses we have not gone over it yet. However, to have an idea of some examples I provided an image below that shows you some shapes with lone pairs. I think it would be good to just see them and have an idea of how they look so when Lavelle does go over it you have some idea of how the shapes with lone pairs look like. Hope that helps :)

wait so for the photo what would 1 lone pair look like for the first row

If you have two atoms attached to the central atom and have 1 lone pair then it would be bent. But if you have only one atom attached to the central atom and 1 lone pair then it would be linear. Here is another chart-like image that I think can help you out more when it comes to lone pairs. That's how I've come to understand it but if I am wrong please correct me.

[Nuoya Jiang]

That would be a bent shape. I believe we'll talk about this in a few days.

[Katherine Chhen 3I]

Ohh so only the number of atoms bound to the central atom determines the molecular shape.

[emma brinton_3B]

It varies depending on the atom of lone pairs. To be honest i would recommend memorizing the VSEPR formula and the shape. Linear models are AX2, AX2E3, and AX2E4.

[Catherine Daye 1L]

A molecule has a linear shape if it is bonded to 2 atoms and has no lone pairs, or bonded to 2 atoms and has 3 lone pairs.

[Snigdha Uppu 1G]

You determine VSEPR based on the regions of electron density, and lone pairs attached to the central atom are considered another region of electron density.

[Kaitlynn Tran 3F]

If it has 0, 3, or 4 lone pairs, the molecular shape will be linear. However, if it has 1 or 2 lone pairs, the molecular shape will be bent.

[Katherine Chhen 3I]

If it has 0, 3, or 4 lone pairs, the molecular shape will be linear. However, if it has 1 or 2 lone pairs, the molecular shape will be bent.

Ohh okay, thank you!

[ramiro_romero]

it will create a bent molecular shape

[Gwen Casillan 3E]

So if the central atom has lone pairs in addition to the bods, then the molecular shape will be bent due to the additional repulsion that the lone pairs have on the other atoms/bonded pair electrons.

[Maika Ngoie 1B]

If the molecule had 1 or 2 lone pairs it would then become bent. If it had 3, that would make it linear

[Aarushi Solanki 4F]

Lone pairs impact the bond angle due to lone pair-bonding pair repulsion, decreasing the angle.