Download Chapter 2 Representative Carbon Compounds: Functional Groups

Chapter 2 Representative
Carbon Compounds:
Functional Groups,
Intermolecular Force, and
Infrared (IR) Spectroscopy
ORGANIC CHEMISTRY
Chapter 2
2.1 Carbon-Carbon Covalent
Bonds
Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY
Chapter 2
Carbon’s ability to form strong covalent bonds to other
carbon atoms is the single property of the carbon atom
that — more than any other—accounts for the
existence of a field of study called organic chemistry.
Carbon’s ability to form as many as four strong bonds
to other carbon atoms, and to form strong bonds to
hydrogen, oxygen, sulfur, and nitrogen atoms as well,
provides the necessary versatility of structure that
makes possible the vast number of different molecules
required for complex living organisms.
Functional groups: The structural features that make it
possible to classify compounds by reactivity. A
functional group is a part of a larger molecule and is
composed of an atom or a group of atoms that have a
characteristic chemical behavior.
Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY
Chapter 2
2.2 Hydrocarbons: Representative
Alkanes, Alkenes, Alkynes, and
Aromatic Compounds
Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY
Chapter 2
Hydrocarbons, are compounds whose
molecules contain only carbon and hydrogen
atoms.
Alkanes: molecules do not have multiple bonds
between carbon atoms.
Alkenes: molecules have a carbon-carbon double
bond.
Alkynes: molecules with a carbon-carbon triple
bond
Aromatic hydrocarbons: molecules contain a special
ring.
Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY
Methane
(an alkane)
Chapter 2
Ethene
(an alkene)
Ethyne
(an alkyne)
Benzene
(a representative aromatic hydrocarbon)
Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY
Chapter 2
2.3 Polar Covalent bonds
δ−
δ+
H Cl
A dipole
Dipole moment (偶极矩)
H Cl
Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY
Chapter 2
2.4 Polar and Nonpolar Molecules
Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY
Chapter 2
H
CH3
C
C
CH3
CH3
C
H
trans-2-butene
µ (D)
CH3
C
H
H
cis-2-butene
mp(°C)
0
−106
0.25
−139
bp(°C)
1
4
Department of Chemistry, Xiamen University