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Solving Problems: A Chemistry Handbook
Chemistry: Matter and Change
231
SOLVING PROBLEMS:
A CHEMISTRY HANDBOOK
CHAPTER 22
8. Write the structure for each of the following.
a. hexanal
b. 4-octanone
Carboxylic acids, esters, and amides A carboxylic acid is an
organic compound that has a carboxyl group. A carboxyl group
(–COOH) consists of a carbonyl group bonded to a hydroxyl group.
Carboxylic acids are polar, reactive, and acidic. They are named by
changing the -ane suffix of the parent alkane to -anoic acid.
Several classes of compounds are derived by replacing the
hydrogen or the hydroxyl group on the carboxyl group with a different atom or group of atoms. In one such compound, an ester, the
hydrogen of the hydroxyl group has been replaced by an alkyl
group. Esters are often polar and sweet-scented. They are named by
first writing the name of the alkyl group, followed by the name of
the acid, with the -ic acid ending replaced by -ate. Esters are frequently made by means of a condensation reaction, a reaction in
which two smaller organic molecules combine to form a more complex molecule, accompanied by the loss of a small molecule such as
water. In the case of esters, the reaction typically occurs between a
carboxylic acid and an alcohol.
An amide is an organic compound in which the –OH group of a
carboxylic acid is replaced by a nitrogen atom bonded to other
atoms. Amide structures are found in proteins. Amides are named by
writing the name of the alkane that has the same number of carbon
atoms and replacing the final -e with the suffix -amide.
Example Problem 22-6
Naming Carboxylic Acids, Esters, and Amides
Classify each compound as a carboxylic acid, an ester, or an amide,
and name the compound.
H C
H
H
H
H
C
H
H O
C N
a. H C
H
H
C
H
H
C
H
H
C OH
c.
O
H C
H
H
C
H
H
C
H
H
C
H
H
C
H
H
H
C O
O
b.
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