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Metamerism | Structural Isomerism

Learning Objective: To learn about metamerism, a subtype of structural isomerism. 

Skill Level – Intermediate

 

Prerequisites: 

Related – 

 

Chapter: Structural Isomerism

 

Author's Note: Same, same, but different. This should be the tagline to describe metamerism, which has the same molecular formula, the same functional group, and the same chemical properties but still differ in their structures. This difference is due to a minor -CH2- group that attaches differently in each isomer. This section covers what metamerism is, various examples of compounds showing metamerism, and the conditions under which they occur in great detail. Understanding metamerism is crucial for predicting and manipulating chemical reactions and physical properties.

Metamerism

Compounds having the same molecular formula but a different number of carbon atoms (or alkyl groups) on either side of the functional group are called metamers, and the phenomenon is called metamerism. 

Metamerism is seen in the members of the same homologous family where the adjacent compounds differ in a -CH2- group. So, these compounds have the same general formula and functional group and, therefore, similar chemical properties.

 

 

Conditions for molecules to show metamerism

1) Number of alkyl groups on either side of the functional group must be different.

2) Only the non-terminal...

..

..

Metamers are also considered position isomers. For example,..

 

Subscribe to learn all subtypes of structural isomerism.

 

Structural Isomerism
Organic Chemistry - Drawing Structures, Concepts, and Examples

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Common Types of Reactions

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Functional Groups in Organic Chemistry

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Structural Isomerism

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Reactive Intermediates

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Stereoisomerism - Conformation and Configurational Isomerism

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