Honors Chemistry
Mr. Fedell
Chapter 22 Notes - Hydrocarbon Compounds and Functional
Groups
(Teacher’s edition)
Suggested Chapter 22 problem set:
You can do many organic problems, but they
aren’t typically a big feature of the SAT II test. It is for this reason that your instructor declines
to even create a list.
NIB - Introduction
“organic”: originally meant that these compounds came from living things.
1828 – Friedrich Wohler (1800 – 1882) synthesized urea (from urine) from inorganic
compounds
now, organic refers to the chemistry of carbon. (except for oxides and carbonates)
General Properties:
There are approximately 2 million organic compounds (last time I checked) and
about 100,000 new ones are created each year.
Organic compounds have generally weak IMF. So… high vapor pressure, low
boiling point, and smell.
Generally don’t conduct, don’t dissolve in water, most burn, and generally slow
reaction rates.
22.1 Organic Compounds:
Bonding:
Carbon makes 4 bonds – sp3 hybridization.
Molecules form long chains resulting in very large molecules.
Isomers are chemicals with the same #’s of atoms, but in a different order (same
formula, different structure).
Ex.
C4H10
Vs.
C4H10
The # of isomers increases with the number of carbon atoms – C1, C2, C3 – 1 isomer,
C4 – 2 isomers, C15H22 – 400 isomers
22.2 – Hydrocarbons
Hydrocarbons – these molecules contain Hydrogen and Carbon ( Uh… hence the name)
open chain (straight):
branch chain:
closed chain (cyclic):
saturated – all single bonds
unsaturated – double or triple bonds
Hydrocarbon Type
Alkanes
Alkenes
Alkynes
Aromatics
Bonds
Single
Double
Triple
Rings
Examples
Propane
Ethene
Ethyne (acetylene)
Cyclopentane
Other examples:
methane, ethane, propane, butane, pentane, hexane, heptane, octane, nonane, decane
Aromatic Hydrocarbons – Hydrocarbon Rings
cyclohexane
benzene
22.4
Organic Reactions
1. polymerization – when simple molecules join to form long chains
natural polymers – cotton, wool, silk, rubber
synthetic polymers – plastic, nylon, rayon
2. Addition reactions
adding halogens is called halogenation
adding hydrogen is called hydrogenation
alkanes:
alkenes:
alkynes:

C 2 H6
+
Cl2
C2H5Cl
+
HCl
C 2 H6
+
2 Cl2 
C2H4Cl2
+
2 HCl
C 2 H6
+
H2

NR
C 2 H4
+
Cl2

C2H4Cl2
C 2 H4
+
2 Cl2 
C2H3Cl3
+
HCl
C 2 H2
+
Cl2

C2H2Cl2
C 2 H2
+
2 Cl2 
C2H2Cl4
C 2 H2
+
3 Cl2 
C2HCl5
+
HCl
note – you can’t hydrogenate an alkane ( why? It’s already saturated) – this is shown in
the examples above
note – you can hydrogenate unsaturated compounds, however examples of this are not
shown above
don’t forget combustion…. “when you just say “CHO”, you make…..CO2 and H2O
22.3 Functional Groups
Name of functional group
General formula
Name/Formula
alcohol
methanol
carboxlyic acid
ethanoic acid
aldehyde
methanal
ketone
propanone
ether
diethyl ether
ester
CH3COOCH3
Picture
NIB – Naming Cycloalkanes and Organic Halides
Alkyl halides
These are important compounds in organic synthesis reactions. For the purposes of nomenclature the
halogens F, Cl,
Br, I are treated as fluoro (not flouro), chloro, bromo and iodo groups.
Name:
Draw:
2,2,3 – tribromopentane
1,2,2,5 - tetrachlorooctane
1,1-diiodo-2-methylprop-1-ene
2-chloro-2-fluoro-3,3-dimethylhexane
Example: Given the formula C2H2Cl2 draw two isomers and name them both.
Cyclic alkanes
1) Name the longest carbon chain in a ring
2) Add the prefix – “cyclo”
Name:
Draw:
Cyclohexene
1,2 – dimethylcyclopropane
5-chloro-2-methylcyclohept-1-yne