Notes On Carboxylic Acids: Nomenclature - CBSE Class 12 Chemistry

Organic compounds that contain the carboxyl functional group (-COOH) are called carboxylic acids.

The name carboxyl is derived from the carbonyl group (C = O) and the hydroxyl group (O-H) of which it is composed.

Higher members of aliphatic carboxylic acids are known as fatty acids.

The common names for carboxylic acids are usually derived from Latin (or) Greek words that indicate the original source of the individual acid. All common names of these acids end with

-ic acid.

Ex: The name formic acid HCOOH is derived from the Latin word 'Formica' which means red ants while acetic acid (CH3COOH) is derived from the Latin word 'acetum' which means vinegar.

Aromatic acids are named as the derivatives of benzoic acid (C6H5COOH).

In the case of substituted acids, the position of the substituent is indicated by the Greek letters alpha, beta, gamma... etc

In the IUPAC system, carboxylic acids are named by replacing the ending 'e' of the corresponding alkane by '-oic' acid to form alkanoic acid.

Ex: The IUPAC name for carboxylic acid containing one carbon is methanoic acid obtained by replacing the ending 'e' of methane by 'oic acid'.

Compounds with more than one carboxyl group are named by retaining the ending 'e' of the alkane and adding the multiplicative prefix di, tri, etc. to the term '-oic' acid.

Ex:

The name of a salt of a carboxylic acid consists of the name of the cation followed by the name of the acid with the ending '-ic' acid being changed to '-ate'.

Ex:

Summary

Organic compounds that contain the carboxyl functional group (-COOH) are called carboxylic acids.

The name carboxyl is derived from the carbonyl group (C = O) and the hydroxyl group (O-H) of which it is composed.

Higher members of aliphatic carboxylic acids are known as fatty acids.

The common names for carboxylic acids are usually derived from Latin (or) Greek words that indicate the original source of the individual acid. All common names of these acids end with

-ic acid.

Ex: The name formic acid HCOOH is derived from the Latin word 'Formica' which means red ants while acetic acid (CH3COOH) is derived from the Latin word 'acetum' which means vinegar.

Aromatic acids are named as the derivatives of benzoic acid (C6H5COOH).

In the case of substituted acids, the position of the substituent is indicated by the Greek letters alpha, beta, gamma... etc

In the IUPAC system, carboxylic acids are named by replacing the ending 'e' of the corresponding alkane by '-oic' acid to form alkanoic acid.

Ex: The IUPAC name for carboxylic acid containing one carbon is methanoic acid obtained by replacing the ending 'e' of methane by 'oic acid'.

Compounds with more than one carboxyl group are named by retaining the ending 'e' of the alkane and adding the multiplicative prefix di, tri, etc. to the term '-oic' acid.

Ex:

The name of a salt of a carboxylic acid consists of the name of the cation followed by the name of the acid with the ending '-ic' acid being changed to '-ate'.

Ex:

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