Question

What is chain isomerism in relation to organic molecules?

Answer 1

The phenomenon of isomerism occurs when two or more compounds have the same chemical formula but distinct chemical structures. Isomers are chemical compounds with similar chemical formulas but differ in characteristics and atom arrangement in the molecule. As a result, substances that display isomers are referred to as isomers. The Greek words "isos'' and "meros," which indicate "equal portions," are used to create the term "isomer." In the year 1830, the Swedish scientist Jacob Berzelius invented the phrase.

Complete answer:
Isomers in chemistry are molecules or polyatomic ions that have the same molecular formula — that is, the same number of atoms of each element — but different atomic configurations in space. Isomerism refers to the existence or potential of isomers.
Isomers don't always have the same chemical or physical characteristics as one another. Structural or constitutional isomerism, in which the bonds between the atoms differ, and stereoisomerism or spatial isomerism, in which the bonds are the same but the relative locations of the atoms differ, are the two primary types of isomerism.
The structural isomers are isomers that differ in the atomic arrangement of molecules without any relation to the spatial arrangement. Structural isomerism is the term for the phenomena of structural isomers. According to the IUPAC, structural isomerism is also known as constitutional isomerism. In contrast to stereoisomerism, it is a type of isomerism in which molecules with the same chemical formula have distinct ordering and bondings.
Chain isomerism, position isomerism, and functional group isomerism are the three kinds of structural isomerism.
Isomerism in Chains: A variation in the atomic arrangement of the carbon to the carbon chain of a molecule is known as chain isomerism. Chain isomerism is a characteristic that occurs when two or more compounds have the same kind of chemical formula but distinct primary chains. Skeletal isomerism is another name for this condition.
Example ${{C}_{4}}{{H}_{10}}$
$C{{H}_{3}}-C{{H}_{2}}-C{{H}_{2}}-C{{H}_{3}}$ and $C{{H}_{3}}-CH(C{{H}_{3}})-C{{H}_{3}}$are chain isomers.

Note:
When there is a variation in the locations occupied by substituent atoms or a group of atoms, or when the chain is unsaturated, positional isomerism occurs. Position isomerism is a phenomenon that occurs when the position of functional groups in relation to the main chain atom changes.
When the odd form of functional groups with the same chemical formula coexist, this is known as functional group isomerism. Functional isomerism is a property of a molecule that has two distinct structures yet the same chemical formula.