In 1911 rutherfurd perform an experiment in order to know the arrangment of electrons and protons in an atom.
Rutherfurd bombarded a very thin gold foil about 0.0004 cm thickness with a-particles. He used a- particles obtained from the disintegration of polonium. A particle are helium nuclei that are doubly positivilycharged ( H++) . Most of these particles passed straight through the foil. Only few particles were slightly deflected. But one in 1 million was deflected through an angle greater than 90° from their straightbpaths. Rutherford performed a series of experiments using thin foil of other elements. He observed similar results from these experiments.
