Question

From the $\alpha$-particle scattering experiment, Rutherford concluded that

• A. $\alpha$-particles can come within a distance of the of ${10}^{-15}m$ of the nucleus.
• B. The radius of the nucleus is less that ${10}^{-15}m$.
• C. The scattering follows Coulomb's law.
• D. The positively charged parts of the atom move with extremely high velocities.

Answer 1

Answer: (A), (B), (C)

The scattering follows Coulomb's law.

From $\alpha$-scattering experiment we have seen in the videos.

What did Rutherford conclude?

Rutherford, on the basis of his observation, drew the following conclusions regarding the structure of atom:

(a) Since most of the $\alpha$-particles passed through the foil undeflected, it indicates that most of the space in the atom is empty.

(b) A few positively charged α-particles were deflected. The deflection must be due to an enormous repulsive force. This shows that the positive charge is not spread throughout the atom as Thomson had presumed. The positive charge is concentrated in a very small volume, which repelled and deflected the positively charged α-particles. Rutherford named this positive centre as nucleus.

(c) Rutherford calculated that the volume occupied by the nucleus is negligibly small as compared to the total volume of the atom. The radius of the atom is about ${10}^{-10}$ m, while that of nucleus is ${10}^{-15}$ m.

Rutherford, on the basis of his observations and conclusions, proposed the nuclear model of atom.

Therefore, options (a), (b) and (c) are correct.