How many lone pairs are present on carbon?

pc

How many lone pairs of electrons (if any) are present on the carbon with negative formal charge?

1 Answer
Oct 26, 2017

There is the ONE lone pair on the carbanion....

Explanation:

#H_3C-CH_2CH_2-CH_2^(-)#

There are 7 electron around the carbanion carbon.....3 electrons from the shared covalent bonds of #C-H# and #C-C#, and TWO electrons based on the carbon, and two inner core electrons (formally the #1s^2# set).

Because the ipso carbon claims 7 electrons, #2# from the lone pair, 2 from the #C-H# bonds, #1# from the #C-C# bond, and #2# inner core, the formal charge of carbon here is #-1#....(the nucular charge of carbon is of course +6, i.e. #Z=6#, and #6-7=-1#)...

Note that this is not a mere formalism: butyl-lithium contains the species as a polar organometallic molecule, and is widely used in organic chemistry, and represents this formalism.