1. Chemistry January 17, 2013 Today's Schedule: Bellringer Jan 17:
Introduce Lewis Dot Diagrams
Homework
Bellringer Jan 17:
1) In your own words, explain covalent bonding. 2) Give an example

2. Lewis Dot Diagrams Bonding occurs with valance electrons (ve-)
Lewis Dot Diagrams: diagrams which show the bonding b/w a molecule and the lone pairs of e- that may exist
We use the chemical symbol of the element and dots to represent electrons
All the other electrons are not shown, only ve-
IN order to study what happens, we need to see what is going on with the ve-. So…we draw Lewis Dot Diagrams.
Gilbert Newton Lewis introduced it in 1916.
Do some single examples

3. Lewis Dot Diagrams- Compounds
In nature, elements are rarely found by themselves. They are typically bonded with something.
Rules for writing Lewis Dot Diagrams:
Determine the # of e- in the species
Write down the central atom (typically least electronegative)
Connect the other atoms to the central atom using single bonds [Subtract from total]
Give surrounding atoms an octet [Subtract from total]
Give “extra” e- to central atom [Subtract from total, leaving zero]
If necessary, shift e- to form double and triple bonds so that central atom has octet

4. QUIZ on Lewis Dot Diagrams TUESDAY!
Homework:
Draw Lewis Dot Diagrams for the following:
Cl F2
K HCl
In 8. CH3I
P SF4
CH H2O
Tomorrow, your sub (Mrs. Lively) will check your homework and introduce you to compounds with double and triple bonds.
QUIZ on Lewis Dot Diagrams TUESDAY!