1. James ChadwickAriana, Colby, and Lindsey 2. Previous model - Rutherford 3. Chadwicks Experiment Chadwick discovered an unknown particle in thenucleus. Predicted by Ettore Majorana, who found itbecause of its lack of electrical charge Chadwick used Rutherfords zinc shield andinferred neutrons do not need to overcome anycoulomb barrier and can therefore penetrate andenter the nuclei of even the heaviest elements. 4. Rutherfordsexperiment 5. Chadwicks Modelft. Bill Nye the Psyence guy 6. Chadwick discovered neutrons in the nucleus,which helped define atoms mass.