How to figure out formal charge?  [ENDORSED]


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Emmy Son 4f
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Joined: Mon Jan 26, 2015 2:17 pm

How to figure out formal charge?

Postby Emmy Son 4f » Sat Jul 16, 2016 5:10 pm

How is formal charge determined?

Chem_Mod
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Re: How to figure out formal charge?

Postby Chem_Mod » Sun Jul 17, 2016 2:33 pm

Formal charge in a lewis structure is determined by the formula:

FC = # valence electrons of atom - [lone pair electrons + 1/2*(bonding electrons)]

Maddy_Larson_2J
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Re: How to figure out formal charge?

Postby Maddy_Larson_2J » Fri Oct 21, 2016 9:19 am

When figuring out a formal charge do we count the individual electrons that are shared or the pairs of electrons that are shared or lone?

Flamingos 3L
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Re: How to figure out formal charge?

Postby Flamingos 3L » Thu Oct 27, 2016 2:39 am

For determining formal charge, it is the number of valance electrons minus the amount of lone electrons and the number of electrons in bonds divided by two. Thus the FC = V - ( L + S/2). A easier way of thinking of the problem in terms of the shared electron is to just consider the number of bonds it has rather than number of electrons in bond divided by two.

Rachel Wile 2D
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Re: How to figure out formal charge?

Postby Rachel Wile 2D » Thu Oct 27, 2016 6:49 am

When calculating formal charge it is easiest just to take the number of valence electrons and subtract the number of bonds (same thing as the number of bonded electrons/2) and subtract the number of lone pair electrons. The resulting number is your formal charge. Do this for each of the atoms of your molecule and then add up all the formal charges to give you the total charge of your atom.

Shreya Ramineni 2L
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Re: How to figure out formal charge?  [ENDORSED]

Postby Shreya Ramineni 2L » Sat Oct 28, 2017 4:27 pm

Formal charge is found by the formula FC= V - (L+(s/2)) where v is the amount of valence electrons of the atom, L is the amount of lone pair electrons, and s/2 is the amount of bonds shared, which can be figured out by divided the electrons shared by 2.

Akash_Kapoor_1L
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Re: How to figure out formal charge?

Postby Akash_Kapoor_1L » Tue Oct 31, 2017 11:20 am

Also make sure that you memorize the equation or know the concept behind calculating formal charge, because Dr. Lavelle said that he won't provide the equation on the reference sheet!!


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