ISOMERISM
It a form or phenomenon which we have compounds forming compound-like formula form the original formula. An isomer of a molecule has the same number of atoms of each element, but has a different arrangement of the atoms. It has the same molecular formula as the other molecule, but with a different chemical structure.
TYPE OF ISOMERISM
11. Structural isomerism.
22. Stereo isomerism.
STRUCTURAL ISOMERISM
It just a phenomenon in which compound exhibits different compound that possesses the same molecular formula but, different structural formula examples include;
11. Straight chain isomerism.
22. Positional isomerism.
33. Functional group isomerism.
44. Chain cycle isomerism.
55. Tautomerism.
66. Metamerism.
STRAIGHT CHAIN ISOMERISM

Isomers are compounds with the same molecular formula but different structural formulae. For example, pentane has three possible isomers in which one is a linear straight-chain alkane and two are branched alkanes.

POSITIONAL ISOMERISM



Positional isomers are constitutional isomers that have the same carbon skeleton and the same functional groups but differ from each other in the location of the functional groups on or in the carbon chain.


FUNCTIONAL GROUP ISOMERISM

Functional isomerism, an example of structural isomerism, occurs substances have the same molecular formula but different functional groups. This means that functional isomers belong to different homologous series.There are two functional group isomers of which you need to be aware: alcohols and ethers.
TAUTOMERISM
Tautomers are isomers of a compound which differ only in the position of the protons and electrons. The carbon skeleton of the compound is unchanged. A reaction which involves simple proton transfer in an intramolecular fashion is called a tautomerism.
METAMERISM
Origin of metamerism. metamer + -ism. Chem. the type of isomerism in which chemical compounds have identical proportions of the same elements and the same molecular weight, but have radicals differing in type or position, with resulting differences in chemical properties.

STEREO ISOMERISM
1.ROTATION ISOMERISM
2.GEOMETRY ISOMERISM
3. OPTICAL ISOMERISM

OPTICAL ISOMERISM
Optical isomers are molecules that differ three-dimensionally by the placement of substituents around one or more atoms in a molecule. Optical isomers were given their name because they were first able to be distinguished by how they rotated plane-polarized light.
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