Isomers are compounds that have the same molecular formula but different structural formulas. This means that they have the same number and types of atoms, but the atoms are arranged differently in the molecule. Isomers can have different physical and chemical properties, such as boiling point, melting point, and reactivity, due to their different structures. There are different types of isomerism, including:

• Structural Isomerism: Compounds that show isomerism due to differences in their structures are known as structural isomers. This phenomenon is known as structural isomerism. Examples of structural isomers include n-butane and isobutane, which have the same molecular formula but different structural formulas.

• Stereoisomerism: This type of isomerism occurs when compounds have the same molecular formula and the same structural formula, but differ in the spatial arrangement of their atoms. Stereoisomers can be further divided into subtypes, such as diastereomers and enantiomers.

• Ionization Isomerism: This type of isomerism occurs when two compounds have the same molecular formula and the same connectivity of atoms, but differ in the way that ions are arranged within the molecule.

Overall, isomerism is an important concept in organic chemistry, as it helps to explain the diversity of organic compounds and their properties.