Carboxylic Acids: Physical Characteristics, Reactivity and Uses

Carboxylic acids are!!!

Organic substances including COOH as a functional group are called carboxylic acids. The group which itself is composed of a carbonyl group(C = O) and a hydroxyl group(-OH) is called a carboxyl group. Carbohydrate from carbonyl and oxyl from hydroxyl.

The carboxylic acid may be an aliphatic or an aromatic depending upon whether is connected to an alkyl group (or a hydrogen atom) or an aryl group.

Carboxylic acids are further categorized as mono, di, tri, or polycarboxylic acids as they contain one, two, three or so on of carboxyl groups respectively in their molecules.

Physical Characteristics of Carboxylic acids

The very first three aliphatic acids i.e., formic acid, acetic acid, and propionic acid are colourless liquids and have a poignant odor. The next three acids C4 to C6 are colourless liquids with a rather unpleasant smell.


Amongst the carboxylic acids, the initial four members are very soluble in water as a result of hydrogen bonding.

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Boiling Point

The boiling points of carboxylic acids are reasonably high due to intermolecular hydrogen bonding. The molecular mass determination in a non-polar solvent like benzene shows that Carboxylic acids exist as cyclic dimers.

Melting Point

The melting points of carboxylic acids boost off-and-on with the increase in molecular mass. It has been observed that the melting points of carboxylic acids including the even number of carbon atoms are higher than the following lower and higher members having the odd number of carbon atoms.

Reactivity of Carboxyl Group

The carboxyl group presents the chemistry of both the carbonyl and the hydroxyl groups. In many reactions of carboxylic acids, the carboxyl group is maintained nonetheless, the reactivity of these molecules is the consequence of the presence of the carbonyl group.

Structure of Carboxylic Group

The carbon and oxygen in the carbonyl are both sp2hybridized which offers a carboxylic acid a trigonal planar form (around the carbonyl carbon) making the bond angles about 120ᵒ.

A resonance structure exists where among the lone pairs of the hydroxyl oxygen (OH) is conjugated with the pi bond of the carbonyl group.

Carboxylic acid, any of a class of natural substances in which a carbon (C) atom is bonded to an oxygen (O) atom by a dual bond and to a hydroxyl group (-OH) by a single bond.

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A fourth bond links the carbon atom to a hydrogen (H) atom or to some other univalent combining group.

Uses of Carboxylic Acids
  • Carboxylic acids and their derivatives are utilized in the manufacturing of polymers, biopolymers, coatings, adhesives, and pharmaceutical medications.
  • They additionally can be used as solvents, preservatives, antibiotics, as well as flavors.
  • Carboxylic acids play considerable functions in the medical field.
  • Carboxylic acid-containing medicines play a major role in the clinical therapy of pain and diseases.
  • They are also used in a wide range of applications as active ingredients in cosmetics.