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Rutherford’s Atomic Model NCERT Chemistry Class 11 Online Notes α-Ray scattering experiment In this experiment, a stream of α particle from a radioactive source was directed on a thin (about 0.00004 cm thick) piece of gold foil. According to Thomson’s model, it was expected that the alpha particles would just pass straight through the gold foil and could be detected by a photographic plate placed behind the foil. But the actual results of the experiment were quite surprising. It was observed that: (i) Most of the α-particles passed straight through the gold foil. (ii) Some of the α-particles were deflected by small angles. (iii) A few particles were deflected by large angles. (iv) About 1 in every 12000 particles experienced a rebound. The results of α-ray scattering experiment were explained by Rutherford in 1911 and another model of the atom was proposed. According to Rutherford’s model, an atom contains a dense and positively charged region located at its centre;