Chapter 2: Structure of Atom (CBSE Class 11)

Introduction

  • The first atomic theory of matter was proposed by John Dalton, in 1808, called Dalton’s Atomic Theory. According to Dalton’s atomic theory, the atom is the ultimate particle of matter and is indivisible.
  • Dalton’s atomic theory was able to explain the law of conservation of mass, the law of constant composition and the law of multiple proportions.
  • Dalton’s atomic theory failed to explain the results of many experiments, for example, “Why does a glass rod or ebonite get electrically charged when rubbed with silk or fur?”

Discovery of Sub-atomic Particles

Atomic Models

Developments Leading to the Bohr’s Model of Atom

Bohr’s Model for Hydrogen Atom

Towards Quantum Mechanical Model of the Atom

Quantum Mechanical Model of Atom