Question

The atom which defines the structure of a family of organic compounds and their properties is called ___________

(a) Resonating structure

(b) Homologous structure

(c) Functional group

(d) Nucleophile

This question was posed to me in unit test.

This interesting question is from Nucleophillic Substitution Reaction topic in section Reactivity of Molecules Reaction Mechanism of Engineering Chemistry I

Answer 1

The correct option is (c) Functional group

Easiest explanation: The atom which defines the structure of a family of organic compounds and their properties is called a functional group.  Functional groups are specific groups of atoms or bonds within molecules that are responsible for the characteristic chemical reactions of those molecules.