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Topic: VSEPR Theorum  (Read 3698 times)

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Offline oilypiggy

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VSEPR Theorum
« on: March 07, 2019, 11:07:29 PM »
Hi Guys, can anyone help with this question?
Using the VSEPR model, the electron-domain geometry of the central atom in NO2- is _______
a) Linear
b)Trigonal Planar
c) Tetrahedral
d)Trigonal Bipyramidal
e)Octahedral

Thanks!

Offline sjb

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Re: VSEPR Theorum
« Reply #1 on: March 08, 2019, 02:00:12 AM »
What are your thoughts? How many electron pairs are there around the central atom?

Offline ChargePositive

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Re: VSEPR Theorum
« Reply #2 on: March 08, 2019, 03:25:34 PM »
Are you able to draw out Lewis structure for the molecule? If you are, classifying the shape is easy, and goes by the number of lone pairs of electrons and bonded pairs of electrons. You can always look up a VSEPR Chart that tells you what shape the molecule will be based on the electron pairs.

Offline oilypiggy

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Re: VSEPR Theorum
« Reply #3 on: March 08, 2019, 08:20:17 PM »
I'm unsure of its 3 or 4 as i dont knwo if the double bond counts

Online AWK

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Re: VSEPR Theorum
« Reply #4 on: March 09, 2019, 03:10:16 AM »
both wrong
You must draw the Lewis structure correctly. Double or triple bonds in the Lewis structure count as "one pair" of electrons for the purpose of establishing the electron pair geometry.
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Offline oilypiggy

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Re: VSEPR Theorum
« Reply #5 on: March 10, 2019, 09:35:29 PM »
Doesn't the lone electron pair count as a domain too

Online AWK

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Re: VSEPR Theorum
« Reply #6 on: March 11, 2019, 03:28:19 AM »
The VSEPR method consists of several rules. I indicated only one that you omitted, indicating an incorrect answer This rule only indicates how to treat multiple bonds, and does not say anything about non-bonding electron pairs or individual non-bonding electrons. Without taking all rules into account, step by step, you will not get a correct answer.
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Offline oilypiggy

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Re: VSEPR Theorum
« Reply #7 on: March 11, 2019, 07:12:49 AM »
I am still incredibly lost, I count 3 electron domains still

Online AWK

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Re: VSEPR Theorum
« Reply #8 on: March 11, 2019, 09:56:13 AM »
So far correct. This excludes c, d, and e.
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Offline oilypiggy

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Re: VSEPR Theorum
« Reply #9 on: March 11, 2019, 06:03:17 PM »
Isn't linear 2 electron domains as well

Online AWK

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Re: VSEPR Theorum
« Reply #10 on: March 11, 2019, 07:19:56 PM »
So the problem is solved.
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Offline oilypiggy

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Re: VSEPR Theorum
« Reply #11 on: March 14, 2019, 09:50:33 PM »
I'm confused, what are you saying the answer is?

Online AWK

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Re: VSEPR Theorum
« Reply #12 on: March 15, 2019, 04:27:22 AM »
 
Quote
I count 3 electron domains still
« Last Edit: March 18, 2019, 09:31:41 PM by Mitch »
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Offline oilypiggy

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Re: VSEPR Theorum
« Reply #13 on: March 15, 2019, 10:19:12 PM »
Isn't trigonal planar for a molecule with no lone pairs though

Offline mjc123

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Re: VSEPR Theorum
« Reply #14 on: March 18, 2019, 09:13:41 AM »
Are you confusing molecular geometry with electron-domain geometry?

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