Question

why is double and triple bond considered as a functional group ?? ( the definition of functional group is * an atom* or a *group of atoms* which replace hydrogen atoms in a hydrocarbon to give its properties , and bonds are'nt group of atoms )

Answer 1

The proper definition of the functional group:

"Groups of atoms or bonds within molecules which determine the chemical properties of the molecule"

According to this Double and triple bond may be regarded as the functional groups.