1. Chapter 25
Organic Chemistry

2. Organic Chemistry Organic Chemistry: Hydrocarbons:
The chemistry of Carbon compounds
Hydrocarbons:
Organic compounds that contain Hydrogen and Carbon only.

3. Carbon can form 4 covalent bonds
2 e- shared between two nonmetals.
Represented by a “─”.

4. Hydrocarbon Prefixes:
IUPAC: International Union of Pure and Applied Chemistry
Hydrocarbon prefixes
meth C
eth C-C
prop C-C-C
but C-C-C-C
Pent C-C-C-C-C
hex C-C-C-C-C-C
hept C-C-C-C-C-C-C
oct C-C-C-C-C-C-C-C
non C-C-C-C-C-C-C-C-C
dec C-C-C-C-C-C-C-C-C-C
Memory device
mosquitos
eat
people’s
blood
meth = 1 carbon
eth = 2 carbons
prop = 3 carbons
but = 4 carbons

5. Types of formulas (Octane)
Molecular
C8H18
(4 covalent bonds “─” per C)
Structural
Condensed
Structural
CH3 ─ CH2 ─ CH2 ─ CH2 ─ CH2 ─ CH2 ─ CH2 ─ CH3
CH3 CH2 CH2 CH2 CH2 CH2 CH2 CH3 or
CH3 (CH2 )6 CH3
Condensed
Carbon
Skeleton
C ─ C ─ C ─ C ─ C ─ C ─ C ─ C
H’s are assumed

6. Types of hydrocarbons Alkanes: All carbon-carbon single bonds. Hexane
Name ends in _____ane
Hexane
Propane
Prop- = 3
Hex- = 6 H H H C H H C C C H 1 2 3 4 5 6 H H H
(Saturated hydrocarbon)

7. Unsaturated hydrocarbons
Alkenes:
Contains at least one carbon=carbon double bond.
Name ends in _____ene
Propene
Prop- = 3
2-pentene
Pent- = 5 H C H H C C C H 1 2 3 4 5 H H H
(Unsaturated hydrocarbon)

8. Unsaturated hydrocarbons
Alkynes:
Contains at least one triple bond.
Name ends in _____yne
Ethyne
(acetylene)
eth = 2
2-butyne
But- = 4 H C H C C H 1 2 3 4
(Unsaturated hydrocarbon)

9. Branched-Chain Alkanes
Parent chain: Longest continuous carbon chain
2-methylbutane
butane H H H H
3-methylbutane 1 2 3 4 H C C C C H 1 2 3 4 H H H
2-methylbutane H C H H
Substituent: Branch off the parent chain substituted for H.
Alkyl groups: attached carbon chains- methyl, ethyl…

10. Branched-Chain Alkanes
Freon molecule: (CFC’s contribute to ozone depletion)
1,1,2-trichloro-1,2,2-trifluoroethane
ethane F F
Parent chain is last word.
Identify
substituent
groups Cl C C F
Substituent groups are named alphabetically 1 2 Cl Cl
Chlorine is called Chloro
Fluorine is called fluoro
Halide: attached halogen family elements-
Fluorine = fluoro, -F
Chlorine = chloro, -Cl
Bromine = bromo, -Br
Iodine = Iodo, I

11. Isomers Pentane C5H12 C5H12 C5H12 2-methylbutane 2,2-dimethylpropane
Isomer: Same molecular formula.
Different structural formula. C H
Pentane
C5H12 C H C H
C5H12
C5H12
2-methylbutane
2,2-dimethylpropane

12. Cis and Trans Isomers Cis Isomer: Trans Isomer: C H Br1 2 3 4 5 6
Cis-3,4-dibromo-3-hexene C H Br
Trans Isomer: C H Br 1 2 3 4 5 6
Trans-3,4-dibromo-3-hexene