Final answer:
A tertiary amine is an organic compound where three carbon atoms are bonded to the nitrogen atom. An example is trimethylamine. The classification of amines is based on the nitrogen's attachment, not the carbon atoms.
Step-by-step explanation:
A tertiary amine is an organic compound where the nitrogen atom is bonded to three carbon atoms (alkyl groups). Unlike primary and secondary amines, a tertiary amine does not have hydrogen atoms attached directly to the nitrogen. A common example of a tertiary amine is trimethylamine, where all three hydrogen atoms of ammonia are replaced by methyl groups (CH₃). In general, the classification of amines is based on the number of alkyl groups attached to the nitrogen atom, not the carbon atoms themselves. This distinction is important because it can affect the chemical properties and reactions that the amine can undergo, for instance, tertiary amines cannot form amides with carboxylic acids but can engage in an acid-base reaction to form ammonium and carboxylate salts.