The Gold Foil Experiment
Rutherford initiated a series of groundbreaking experiments that would completely change the accepted model of the atom. They bombarded very thin sheets of gold foil with fast moving alpha particles. Alpha particles, a type of natural radioactive particle, are positively charged particles with a mass about four times that of a hydrogen atom.
Rutherford’s atomic model became known as the nuclear model. In the nuclear atom, the protons and neutrons, which comprise nearly all of the mass of the atom, are located in the nucleus at the center of the atom. The electrons are distributed around the nucleus and occupy most of the volume of the atom. It is worth emphasizing just how small the nucleus is compared to the rest of the atom.
Rutherford’s model proved to be an important step towards a full understanding of the atom.
Bombardment of gold foil with alpha particles showed that some particles were deflected.
The nuclear model of the atom consists of a small and dense positively charged interior surrounded by a cloud of electrons.