Definition
A Carboxylic Acid is an organic compound containing a carboxyl
functional group. They occur widely in nature and are also synthetically
manufactured by humans. Upon deprotonation, carboxylic acids yield
a carboxylate anion with the general formula R-COOH–, which can form
a variety of useful salts such as soaps.
Carboxylic Acid Structure
The general formula of a carboxylic acid is R-COOH, where COOH refers
to the carboxyl group, and R refers to the rest of the molecule to which
this group is attached. In this carboxyl group, there exists a carbon
which shares a double bond with an oxygen atom and a single bond
with a hydroxyl group.
The first four carboxylic acids derived from alkanes are methanoic acid
(HCOOH), ethanoic acid (CH3COOH), propanoic acid (C2H5COOH), and
butanoic acid (C3H7COOH).
Nomenclature of Carboxylic Acids
1 Common system : Common name are given from the source
from which they have derived. Like Formic acid was derived
from red ant (ants = Formica).
2. Derived system: According to this system some monocarboxylic acids
are named as alkyl derivatives of acetic acid.
𝐶𝐻3 − 𝐶𝐻2 − 𝐶𝑂𝑂𝐻
Methyl acetic acid
3. IUPAC system
a. Monocarboxylic acid : The longest chain of carbon atoms including
-COOH in monocarboxylic acid is considered as parent chain and is
named by replacing the -e of the corresponding parent alkane with -oic
acid.
Ex- Alkanoic acid
b. Dicarboxylic acid: Dicarboxylic acid is Alkanedioic acid. The suffix
dioic acid is added to the name of parentalkane containing the same
number of carbon atom
HOOC-COOH Ethanedioic acid
HOOC-CH2-COOH Propanedioic acid etc
c. Tricarboxylic acid
If more than two crboxyl group are bonded to unbranched carbon chain
than carbon atom of the carboxyl group are not incuded in the parent
chain.
Example
Preperation of carboxylic acid
Preperation from primary alcohols
Physical properties of mocarboxylic acid
 Forst four member are highly soluble in water
 Lower member are pungent smeeling liquid other are
rotten butter smelling and higher member are colourless.
Chemical properties of monocarboxylic acid