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Formal Charge on Sulfate
Started by ManzRDH
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ManzRDH said:Sulfate (SO4)-2
Can someone exlain the formal charge on oxygen?
I found sulfur's formal charge to be 2 which is correct
Formal Charge= V -1/2 N bonding- N non-bonding
Wow you are having a hard time huh? What exactly are you studying with?
O is always -2
there are 4 Oxygens. 4 x -2 = -8
the sum of the oxidation numbers must = -2
so Sulfur must be 6 !
-8 + 6 = -2
get it?
First, congrats on knowing the difference between formal charge and oxidation number, unlike vertical bite. 👍ManzRDH said:Sulfate (SO4)-2
Can someone exlain the formal charge on oxygen?
I found sulfur's formal charge to be 2 which is correct
Formal Charge= V -1/2 N bonding- N non-bonding
It's easiest if you draw the Lewis dot structure for sulfate...I can't do it on the computer here...
But, you're right, the equation to calculate the formal charge is:
# of valence electrons - # of non bonding electrons - (1/2)*# of bonding electrons.
Look at the Lewis dot structure. . .
For the S, you have 6 valence electrons, 0 nonbonding electrons, and 8 bonding electrons....plug these values into the question and you get 2, like you said.
6 - 0 - (1/2)*8 = 2
For O, you have 6 valence electrons, 6 nonbonding electrons, and 2 bonding electrons....plug these values into the question and you get -1
6 - 6 - (1/2)*2 = -1
OH I got burned !!!
Finally someone in these forums with brains.
Ugly dog but brains.......
Finally someone in these forums with brains.
Ugly dog but brains.......
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And oxygen's oxidation number is not always -2.drat said:First, congrats on knowing the difference between formal charge and oxidation number, unlike vertical bite. 👍

Good god who cares ????
Ok I think its gonna be darn rare to see a peroxide question.
MAn.............................
Ok I think its gonna be darn rare to see a peroxide question.
MAn.............................
luder98 said:And oxygen's oxidation number is not always -2.![]()
'Tis true. Peroxides are the exception where O is -1. But it wasn't me who said O is always -2!! Don't go mixing me and Vert up. I'm utterly offended. 🙂
But, let's not talk about oxidation 'cause the OP had a question about formal charge...No need for confusion -- but it's important to recognize there IS a difference!
Peroxides?
I posted that above you.
READ.
I swear its hard being so smart.
I am in dental school. are you ?
I posted that above you.
READ.
I swear its hard being so smart.
I am in dental school. are you ?
drat said:'Tis true. Peroxides are the exception where O is -1. But it wasn't me who said O is always -2!! Don't go mixing me and Vert up. I'm utterly offended. 🙂
But, let's not talk about oxidation 'cause the OP had a question about formal charge...No need for confusion -- but it's important to recognize there IS a difference!
Id bet $100 that you have to look that up..........
vertical bite said:Id bet $100 that you have to look that up..........
okay. i win. i'm awesome. go me. i'm a chemist so if i didn't know the answer to that question, i'd be pretty pathetic. but i'm willing to entertain other chemistry questions if you'd like to try and stump me.

drat said:okay. i win. i'm awesome. go me.
i'm a chemist so if i didn't know the answer to that question, i'd be pretty pathetic. but i'm willing to entertain other chemistry questions if you'd like to try and stump me.![]()
Well good stuff then.
I rem. it too but have never seen it EVER come up so sue me.

Of course I knew that it wasn't you. I only wanted to add to your comment. BTW, it can also be +1 when it's in a compound with a more electronegative element like F. I do not want to outsmart anyone here because I know I'm just an average Joe and there are plenty of people (you are one of those) on this forum who are definitely smarter/better than me. I'm sure you know my intention.drat said:'Tis true. Peroxides are the exception where O is -1. But it wasn't me who said O is always -2!! Don't go mixing me and Vert up. I'm utterly offended. 🙂
But, let's not talk about oxidation 'cause the OP had a question about formal charge...No need for confusion -- but it's important to recognize there IS a difference!
luder98 said:Of course I knew that it wasn't you. I only wanted to add to your comment. BTW, it can also be +1 when it's in a compound with a more electronegative element like F. I do not want to outsmart anyone here because I know I'm just an average Joe and there are plenty of people (you are one of those) on this forum who are definitely smarter/better than me. I'm sure you know my intention.
Ah yes, I suppose that is the case for OF2 and such. Good stuff, luder98. Hadn't really thought of that!! I love chemistry!
But for future DAT takers, don't worry about such a rare occurance! 🙂