The First Model of an Atom was given by (A) N. Bohr (B) E. Goldstein (C) Rutherford (D) J.J. Thomson

Answer: (D) J.J. Thomson

J. Thomson, a British physicist, was the first to propose an atomic model in 1900 named as plum pudding model depicting it as a sphere of positive matter with electrons positioned by electrostatic forces. As a result, he not only identified the electron but also established that it is an essential component of an atom.

Postulates of his atomic model were:

• A positively charged sphere with electrons contained in it makes up an atom.
• As the negative and positive charges are of equal magnitude, an atom is electrically neutral as a whole.