Lecture 1: Functional groups, lewis structures, formal charge

Formal Charge

# of valence electrons - bonds - dots

alcohols

ROH, at the end of carbon chain

Ethers

ROR, in the middle of carbon chain

aldehydes

RCHO, at the end of carbon chain

ketones

RCOR, in the middle of carbon change

Carboxylic acids

RCOOH, at the end of carbon chain

esters

RCOOR, in the middle of carbon chain

amines

R3N

1 carbon

methane

2 carbons

ethane

3 carbons

propane

4 carbons

butane

5 carbons

pentane

6 carbons

hexane

7 carbons

heptane

8 carbons

octane

9 carbons

nonane

10 carbons

decane

Figuring out lewis structure

1) Central atom (less electronegative except H)

2) Draw bonds around central atom

3) total # valence electrons

4) Distribute them around terminal atoms (except H)

5) Octet rule!

6) Formal charge to minimize charge and obey octet rule