Chemistry 231 – Elementary Organic Chemistry
Problem Set – The Structure of Molecules
1. For each of the given molecular formulae, draw the most stable (lowest energy) Lewis Dot
Structure.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
NH2OH
H2CO3
H3PO3
SO3
POCl3
CHNO
CHNS
HCN
SO2
HN3
2. For each of the given molecular formulae, draw the most stable (lowest energy) Lewis Dot
Structure.
a.
b.
c.
d.
e.
f.
g.
h.
H2SO4
(CO2H)2
HNO2
H2O2
HClO4
Cr2O72P2O74N2O4
3. For each of the following compound names, draw a corresponding line structure. Be certain to
indicate absolute stereochemistry.
a.
b.
c.
d.
e.
f.
1-methyl-1-bromocyclopentane
3,3-dimethyl-1-butene
(S)-1-bromo-1-iodomethane
1,5-diazabicyclo[4.3.0]non-5-ene
meso-1,3-diethylcyclohexane
n-butyllithium
4. For each of the following compound names, draw a corresponding line structure. Be certain to
indicate absolute stereochemistry.
a.
b.
c.
d.
e.
Cyclohexyl fluoride
n-Butyl bromide
tert-Pentyl chloride
Allyl chloride
Benzyl iodide
5. Write a valid Lewis structure for each of the following compounds:
a. Amide anion, NH2b. Nitrous oxide (laughing gas), N2O (arranged N—N—O)
c. Bicarbonate anion, HCO36. For each of the compounds shown below, draw all valid resonance structure. Circle the most
important structure that contributes to the overall resonance hybrid.
a.
b.
c.
7. Ozone is an allotrope of oxygen. Its molecular weight is 48.0 g mol-1.
a. What is the molecular formula of ozone?
b. Draw a valid Lewis structure for the formula indicated above. Be certain to indicate formal
charges (if any) within the molecule.
c. Are there any resonance forms of ozone that correspond to your structure from part (b)? If so,
what are they and how are they formed?