Everything Science Grade 12

1.10 CHAPTER 1. ORGANICMOLECULES

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(1.) 01p3

Derivatives of carboxylic acids: The

esters

ESCZ

When an alcohol reactswith a carboxylic acid,an ester is formed. Most estershave

a characteristic smell.In the reaction, the hydrogen atom from the hydroxyl group,

and an OH from the carboxlic acid, form a molecule of water. A newbond is formed

between what remains of the alcohol and acid. The name of the ester is acombination

of the names of the alcohol and carboxylic acid. The suffix for an ester is -oate. An

example is shown in figure 1.23.

H C

H

H

O H+H O C H

O

H C

H

H

O C H

O

+ H 2 O

methanol methanoic acid methyl methanoate

Figure 1.23: The formation of an ester and water from an alcohol and carboxylic acid

1.10 The Amino Group.

The amino group has the formula -NH 2 and consists of a nitrogen atom that is bonded

to two hydrogen atoms,and to the carbon skeleton. Organic compounds that contain

this functional group are called amines. One example is glycine. Glycine belongs to

a group of organic compounds called amino acids, which are the building blocks of

proteins.