I would think so, eliminating the 1 extra electron, P(5 valence)-4(bonds) making a plus 1 formal charge.
with that said, can a central atom have only one excess electron as oppose to the a pair?
As a radical, yes.
P(CH3)4 would indeed have a formal charge of +1 on phosphorous. I think they're not putting the formal charge for a reason just so you could figure it out (or else why ask that question at all?)
you mean P(CH3)4 + would have a formal charge or +1 on P right? because as you said you could have a radical species where the formal charge on P would be 0.
why ask the question at all? just because you have a charged species does not automatically put the formal charge on the central atom. See the sulfate ion lewis. Likewise you can have a neutral species with formal charges that cancel each other out. See carbon monoxide lewis.
Could somebody please confirm that this question from destroyer is wrong / right so this can be resolved????
Formal charge is Group # - ( 1/2 # shared electrons- # unshared electrons). Thus,.,,,, 5- ( 1/2 (8) - 0 )= 1 Thus molecule has no formal charge.
i hope this helps
But that's for the entire molecule. We want the formal charge of Phosphorus.
P wants 5 electrons, but there's only 4 electrons bonded to it. Therefore, 5-4 = +1.
By the way, forget the formal charge equation. This is the general equation I use:
What an element "wants" (valence electrons) minus the actual number of electrons bonded to element = formal charge.
For example what is the formal charge of N in NH3?
N wants 5 electrons and has 5 electrons (2 electrons from the lone-pair + 3 electrons from the N-H bond). Therefore, 5-5 = 0.
What about ammonium NH4?
N wants 5 electrons and has 4 (there's no lone-pair electrons on NH4). Therefore, 5-4 = +1.
I hope that clears it up!
I really do appreciate your help but no its not cleared up. Ammonium without the +1 charge? I think you understand that there is no such thing as NH4 without the +1 charge. It is a violation of the octet rule. the reason the Phosphorous compound can exist as a neutral species is bc it can have expanded octets.
I will just assume destroyer made a typo and forgot to put in the +1 charge in the question.
I just edited my post. I accidentally hit "submit reply."
It's not a typo. Destroyer is absolutely correct. Look up the Lewis Dot Structure of Tetramethylphosphonium Chloride if you have any doubts. It's a tetrahedral structure. The extra electron on P gives it a positive charge.
Please please please go to the top of the thread and view the original question straight out of destroyer. Where do you see a Chlorine atom in the structure? The compound you are refering to is an IONIC compound formed from the Pch3 4 cation and a chlorine anion. The compound destroyer is referring to is neutral. For your own benefit you have to know why this is a mistake. P ch3 4 as a neutral species exists as a radical. In which case the charge on P is 0 and destroyer is wrong.
Here you go buddy!
http://www.chemicalbook.com/ProductChemicalPropertiesCB6385341_EN.htm
That's why it's a +1 charge.
There is just no getting through to you. Are you even reading these posts? The compound you are showing me is tetramethyl phospONIUM. It is a CATION. Like H30+ (i.e. HydrONIUM) or NH4+ (i.e. ammONIUM). The question originally asks for the charge on P for P(CH3)4 or Tetramethyl Phosphorous. The charge on P here is 0 and it exists as a radical. nevermind.
Do you understand that P(CH3)4 and P(CH3)4 + are NOT the same thing. And that the formal charges on P are 0 and +1 respectively. If this question appears on your exam (or one just like it) you will choose the wrong answer.
Can we at least agree that P(CH3)4 and P(CH3)4 + are not the same compound?
