Question

State two conclusions from Rutherford's scattering of alpha particles with gold foil.

Answer 1

Two conclusions from Rutherford's scattering of alpha-particles $\left({}_2{}^4\mathrm{He}^{+2}\right)$ with Gold (Au) foil are:

(1) Most of the space inside the atom is empty.

• This conclusion was based on the observation that most of the alpha-particles on bombardment with the thin gold foil passed straight through the foil without any change in their path.

(2) There is a dense mass of positive charge concentrated in the centre of an atom.

• This conclusion was drawn from the observation that a few alpha-particles deviated from their path by small angles and an even lesser number of particles completely rebound on hitting the gold foil. This was possible if the positively charged alpha-particles had hit something positive which is confined in a small volume inside an atom.