Question

I am having a lot of trouble looking at structures and figuring out how many lone pairs there is or formal charges.

Here is the link to the diagram.
http://www.webassign.net/userimages/kasandbe@ncsu/CH221_ssii_02/ch221_ssii04_HW1aa.gif
Each atom is indicated by a letter. I have to know how many lone pair (s) and the formal charge of each atom.

Any help is appreciated!

Answer 1

Can't see the image, but generally for organic molecules you can just use the octet rule. Every atom (except H) is going to have four pairs of electrons around it. Count the number of pairs you see present as bonds (one per single bond, two per double bond, three per triple bond) and subtract from four. The result is the number of lone pairs.

This won't work for more complicated structures involving Period 3 or higher atoms that violate the octet rule, but in those cases lone pairs are normally written explicitly.