Explain the term with example : Functional group

Explanation

i.An atom or group of atoms which determines specific chemical properties of a compound is called a functional group.
ii. Functional group may or may not contain hetero atoms in them.
E.g.
a. In `CH_(3)-OH,-OH` (alcohol) is the functional group.
In `CH_(3)-CH=CH-CH_(3)`, double bond `(-overset(|)C=overset(|)C-)` is the functional group.