Experiment -particle bombardment of gas B products bombard paraffin wax behind target Results knocked out of paraffin protons Inference 1. En transferred to by massive particle protons 2. (from proton tracks) mn mp a 2nd nuclear particle with proton mass but no charge complete atomic model P.S. 1932: nucleus contains protons and neutrons electrons orbit atomic nucleus explains atomic structure, isotopes, radioactivity e.g. 3. Radioactivity element uranium producing mysterious radiation that Becquerel (1896): could penetrate black paper and fog photographic film - independent of temp, press, E-field Becquerel radiation contains 3 components Rutherford (1900): and rays α,β γ rays: massive particles of double +ve charge α rays: same as electrons q/m β rays: similar to but higher energy and penetration X-rays, γ Rutherford and Soddy (1903): some atoms can spontaneously disintegrate
Experiment -particle bombardment of B gas products bombard paraffin wax behind target Results protons knocked out of paraffin Inference 1. En transferred to protons by massive particle 2. mn mp (from proton tracks) a 2nd nuclear particle with proton mass but no charge P.S. 1932: complete atomic model nucleus contains protons and neutrons electrons orbit atomic nucleus explains atomic structure, isotopes, radioactivity e.g. 3. Radioactivity Becquerel (1896): element uranium producing mysterious radiation that could penetrate black paper and fog photographic film - independent of temp, press, E-field Rutherford (1900): Becquerel radiation contains 3 components α,β and γ rays α rays: massive particles of double +ve charge β rays: same q/m as electrons γ rays: similar to X-rays, but higher energy and penetration Rutherford and Soddy (1903): some atoms can spontaneously disintegrate
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