On the basis of Thomson's model of an atom, explain how an atom as a whole is neutral.

Which sub-atomic particle was discovered by

(a) Thomson

(b) Goldstein

(c) Chadwick.

(a) Which metal did Rutherford select for his α-particle scattering experiment and why ?

(b) What do you think would be the observation of α-particle scattering experiment if carried out on

(i) heavy nucleus like platinum

(ii) light nuclei like lithium.

On the basis of Rutherford's model of an atom, which subatomic particle is present in the nucleus of an atom?