MENTS 1. Pre-Lab Assignment
2. Data Sheet
3. Post-Lab Assignment
VIDEO CLIPS
Dr Dan Videos on Molecular Models - will be provided on Canvas
LABWARE & CHEMICALS
Molecular Model Kit
.
PROCEDURE(S)
A. DRAWING LEWIS DOT STRUCTURES
Drawing Lewis structures takes time and practice, and there is no single set of steps that
will always yield the correct answer. Expect to occasionally draw several incorrect
models before you find the correct one. Learn from each incorrect model
what does and
does not work, and apply it to drawing future Lewis structures. The general rules below
will generally lead to the correct structure in one or two attempts.
Perform the following:
1. Add up the valence electrons
a) Add up the valence electrons for all atoms (s and p orbitals with the highest
quantum number)
b) Add electrons for molecules with a negative charge (eg: CO32-)
c) Subtract electrons for molecules with a positive charge (eg: NH4+)
2. Write a trial structure
a) Place the least electronegative atom in the center
58