Question

define isomerism, functional group, homologous series..?

Answer 1

Isomerism is the property in which two or more compounds or ions that are composed of the same kinds and numbers of atoms but differ from each other in structural arrangement (structural isomerism) as CH3 OCH 3 and CH 3 CH 2 OH, or in the arrangement of their atoms in space and therefore in one or more properties.
An atom or group of atoms which show a characteristic unique reactivity when treated with some reagents and also which impart some unique chemical as well as physical properties to the primary molecule is defined as  a functional group.
A homologous series is a series of compounds with the same general formula

Answer 2

The compound having same molecular formula but different physical and chemical properties are called Isomers and this phenomenon is called isomerism

a series of organic compound having same functional group in which two successive members differ from each other by 6 number of carbon and hydrogen. search series of organic compound are called h********* series.

a group of atom responsible for the characteristic reaction of a particular compound is called functional group.