Alpha Particle Scattering Experiment - GCSE Chemistry Definition

The Alpha Particle Scattering Experiment, conducted by Ernest Rutherford in 1909, is a pivotal experiment that led to the discovery of the atomic nucleus. In this experiment, alpha particles, which are positively charged, were directed at a thin sheet of gold foil.

Most of the alpha particles passed straight through the foil, but some were deflected at various angles, and a few even bounced back towards the source. This surprising result led Rutherford to propose that atoms consist mostly of empty space with a small, dense, positively charged nucleus at the centre.

This experiment was fundamental in moving away from the "plum pudding" model of the atom and developing the nuclear model, where electrons orbit the nucleus, and it significantly advanced our understanding of atomic structure.