VSPER Formula

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

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Victoria Luu - 1C
Posts: 60
Joined: Fri Sep 28, 2018 12:15 am

VSPER Formula

Postby Victoria Luu - 1C » Mon Nov 19, 2018 9:42 pm

What does the A stand for in the VSPER Formula? What can you use the formula to find out?

Jeannine 1I
Posts: 73
Joined: Fri Sep 28, 2018 12:27 am

Re: VSPER Formula

Postby Jeannine 1I » Mon Nov 19, 2018 9:47 pm

The VSEPR formula refers to AX(sub n)E(sub m), where A is the central atom, X is the atoms attached to the central atom (so n would be the number of atoms attached), and E refers to electron lone pairs (so m would be the number of lone pairs attached to the central atom). For example, in H20, the VSEPR formula would be AX2E2 since there are two hydrogen atoms and two lone pairs attached to the central oxygen atom.

The VSEPR formula helps you remember the names of the molecular geometry shapes!

Alexandra Albers 1D
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Joined: Fri Sep 28, 2018 12:18 am

Re: VSPER Formula

Postby Alexandra Albers 1D » Mon Nov 19, 2018 9:51 pm

The AXE structure in VSEPR theory is essentially just a template, so that if you can remember how one molecule with that particular structure looks, you will know the shape of all molecules of that model.

Sean Reyes 1J
Posts: 67
Joined: Fri Sep 28, 2018 12:24 am

Re: VSPER Formula

Postby Sean Reyes 1J » Tue Nov 20, 2018 6:50 pm

"A" is simply the notation for the central atom.
"X" stands for the amount of bonded atoms (not bonds total, the amount of atoms attached)
"E" is the number of lone pairs.
For example, the VSEPR formula for CH4 would be AX4 since there are no lone pairs on the carbon and because each hydrogen is bound to the carbon.

105002507
Posts: 30
Joined: Fri Sep 28, 2018 12:15 am

Re: VSPER Formula

Postby 105002507 » Tue Nov 20, 2018 11:01 pm

A just stands for the central atom!

Samantha Chang 2K
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Joined: Fri Sep 28, 2018 12:17 am

Re: VSPER Formula

Postby Samantha Chang 2K » Tue Nov 20, 2018 11:57 pm

A stands for the central atom!

Helen Mejia 1I
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Joined: Fri Sep 28, 2018 12:24 am

Re: VSPER Formula

Postby Helen Mejia 1I » Wed Nov 21, 2018 1:12 pm

The A in the VSEPR formula stands for the central atom.

Ashita Tanwar 3H
Posts: 30
Joined: Fri Sep 28, 2018 12:23 am

Re: VSPER Formula

Postby Ashita Tanwar 3H » Sat Nov 24, 2018 12:41 am

If the AXE formula is a template, does it change/become more specific when referring to a particular molecule? Or will it always be AXE?


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