AXE formula

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danielruiz1G
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Joined: Fri Apr 06, 2018 11:04 am

AXE formula

Postby danielruiz1G » Sun Jun 03, 2018 10:51 pm

is it possible to determine the shape of a molecule if you're only given the AXE formula, if so how do you do it?

Jessica Urzua-1H
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Re: AXE formula

Postby Jessica Urzua-1H » Sun Jun 03, 2018 10:54 pm

It is possible. The AXE formula tells you how many regions of electron density there are, which ones are specifically bonding pairs, and which ones are lone pairs. This is all that is needed to determine molecular shape.

Jack Martinyan 1L
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Re: AXE formula

Postby Jack Martinyan 1L » Sun Jun 03, 2018 10:57 pm

The chart below will be helpful
Attachments
vsepr handout part 2.jpg
vsepr handout.jpg

Enzo_1I
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Re: AXE formula

Postby Enzo_1I » Sun Jun 03, 2018 10:58 pm

From what i understand it is necessary to know the shape that corresponds to the formula. This means memorizing which formulas are associated to which shape.

Patience Olsen 1A
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Re: AXE formula

Postby Patience Olsen 1A » Sun Jun 03, 2018 11:04 pm

Yes. A represents the center atom, X represents atoms bonded to the center atom, and E represents lone electron pairs. X and E together represent regions of electron density.
Each AXE formula corresponds to a different molecular structure shown in the chart posted by Jack.

Miya Lopez 1I
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Re: AXE formula

Postby Miya Lopez 1I » Sun Jun 03, 2018 11:05 pm

I believe if they give you the molecular formula and the AXE formula you could determine the shape. Say if you were given H2O: AX2E2... then you know there are 2 bonding atoms and 2 lone pairs. Then once you draw the molecule out you could figure out its shape.

Daniela Alvarado 3B
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Re: AXE formula

Postby Daniela Alvarado 3B » Sun Nov 18, 2018 11:00 pm

Enzo_1I wrote:From what i understand it is necessary to know the shape that corresponds to the formula. This means memorizing which formulas are associated to which shape.


do you happen to know if theres anyway to know the corresponding shape aside form the AXE formula? or must we memorize those too?

Rachel Dang 1H
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Joined: Fri Sep 28, 2018 12:17 am

Re: AXE formula

Postby Rachel Dang 1H » Mon Nov 19, 2018 1:16 pm

There really isn't another way, the best thing to do is just memorize them because the AXE formula tells you what shape the molecule is.

Rami_Z_AbuQubo_2K
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Re: AXE formula

Postby Rami_Z_AbuQubo_2K » Fri Nov 23, 2018 8:36 pm

The only way for you to know the shapes is to simply memorize them using the table above or one that you can search up online. By knowing AXE, that should in turn help you figure out the different geometric shapes of each molecule.

Kyither Min 2K
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Re: AXE formula

Postby Kyither Min 2K » Wed Nov 28, 2018 9:09 pm

Yes. With the AXE formula you can deduce what shape and bond angle the molecule will have based on charts and tables.

Schem_student
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Re: AXE formula

Postby Schem_student » Sat Dec 01, 2018 3:16 pm

Also be aware that AXE is a specific VSEPR Group that will help you determine MG or molecular geometry.

Erin Kim 2G
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Re: AXE formula

Postby Erin Kim 2G » Sat Dec 01, 2018 5:19 pm

yes you can determine the molecular shape of the molecule, knowing the AXE formula because the number of electron densities are known. By counting the number of lone pairs and the number of atoms around the central atom you can know the shape and bond angles.

005115864
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Re: AXE formula

Postby 005115864 » Sat Dec 01, 2018 5:40 pm

It's possible but be aware of that there are molecules with different shapes but same AXE Formula. This is because they have the same number of electron densities. For instance, tetrahedral and trigonal pyramidal are both AXE4 because they both have 4 regions of electron densities.

SydBenedict2H
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Joined: Wed Nov 08, 2017 3:00 am

Re: AXE formula

Postby SydBenedict2H » Sat Dec 01, 2018 8:10 pm

To learn these I just made a chart, or you can write down the one posted above as it can be super helpful, and then put it all into flashcards on quilt. I studied that until i had it memorized, then, doing a bunch of problems switches the memorization from route to actual understanding.

Phil Timoteo 1K
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Re: AXE formula

Postby Phil Timoteo 1K » Sun Dec 02, 2018 8:00 pm

Yes with the AXE formula you can determine the shape of the molecule

Lauren Huang 1H
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Joined: Fri Sep 28, 2018 12:16 am

Re: AXE formula

Postby Lauren Huang 1H » Mon Dec 03, 2018 6:00 pm

Yes, the AXE formula can help you draw the shape of the structure, but it will not tell you the elements involved.

Arlene Linares 3A
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Re: AXE formula

Postby Arlene Linares 3A » Mon Dec 03, 2018 8:27 pm

How do we figure out the AXE formula? I am still having trouble with this.

Jack Hewitt 2H
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Re: AXE formula

Postby Jack Hewitt 2H » Thu Dec 06, 2018 6:03 pm

danielruiz1G wrote:is it possible to determine the shape of a molecule if you're only given the AXE formula, if so how do you do it?

Yes because the AXE formula tells you the regions of electron density which is all you need to determine the shape.

Jack Hewitt 2H
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Joined: Fri Sep 28, 2018 12:27 am

Re: AXE formula

Postby Jack Hewitt 2H » Thu Dec 06, 2018 6:05 pm

Arlene Linares 3A wrote:How do we figure out the AXE formula? I am still having trouble with this.

A is the central atom. X is the number of atoms bonded to the central atom. E is the number of lone pairs on the central atom.

Zachary Menz 1D
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Joined: Wed Nov 07, 2018 12:17 am

Re: AXE formula

Postby Zachary Menz 1D » Sat Jul 20, 2019 6:25 pm

Yes, you can determine shape with the AXE formula. You should try to memorize them because it'll save time and guarantee correctness on exams, but you can also think about it in terms of regions of electron density, where X represents bonding pairs on the central atom and E represents lone pairs on the central atom.


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