Why was Thomson’s Model of an atom failed?
i. It could not explain the screening of negative charges from that of positive
ii. It did not tell about the presence of electrons
iii. It did not give an idea about the position of the nucleus
iv. It explained the atom as a whole to be electrically neutral.
Both (i) & (iii)
Thomson model of an atom could not explain the stability of an atom, i.e., how a positive charge in the atom holds the negatively charged electrons. It could not explain the position of the nucleus in an atom and the scattering of alpha particles.