Page 1 - 3. LESSON NOTES-(RUTHERFORD'S ALPHA PARTICLE SCATTERING EXPERIMENT & DISCOVERY OF NUCLEUS)
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SAI International School
                                                Subject-Chemistry

                                            Ch-Structure of the Atom
                    Topic- Rutherford’s alpha particle scattering experiment and
                                               discovery of nucleus

                                                   Lesson Notes
               Rutherford’s Alpha particle Scattering Experiment

                 He experimented with thin gold foil by passing alpha rays through it.

                 Alpha particle, positively charged particle, identical to the nucleus of the Helium
                  atom. It carries double positive charge. The symbol used for alpha particle is α, α ,
                                                                                                       2+
                     2+
                  He
                 Gold foil was chosen for the experiment as it is the most malleable metal.
                 He expected that the gold atoms will deflect the Alpha particles.



























                               Observations                                         Inferences



             Alpha particles which had high speed moved           Atom contains a lot of empty space
             straight through the gold foil


                                                                  Positive charges in the atom are not
             Some particles got diverted a by slide angles
                                                                  occupying much of its space



                                                                  The positive charges are concentrated over
             Only one out of 12000 particles bounced back
                                                                  a particular area of the atom.






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