Discovery of the Nucleus: Protons and Neutrons

1. Discovery of the Nucleus: Protons and Neutrons By: Isaac, Noah, Jon

2. Ernest Rutherford • Rutherford described his 'neutral doublet', or neutron, in 1920. The particle would be uncharged but with a mass only slightly greater than the proton. Because it was unchargedthere would be no electrical repulsion of the neutron as it passed through matter, so it would be much more penetrating than the proton. This would make the neutron difficult to detect.

3. James Chadwick • James Chadwick was an English physicist who was awarded the 1935 Nobel Prize in physics for his discovery of the neutron in 1932. He was the head of the British scientistswho worked on the Manhattan Project during World War II.

4. Hans Geiger • Johannes "Hans" Wilhelm "Gengar" Geiger was a German physicist. He is perhaps best known as the co-inventor of the Geiger counter and for the Geiger–Marsden experiment which discovered the atomic nucleus.

5. Ernest Marsden • Following the war he became New Zealand's leadingscientist, founding theDepartment of Scientific andIndustrial Research (DSIR) in 1926 and organizing its research particularly in the area ofagriculture. DuringWorldWar II he worked on radar research and in 1947 becamescientific liaison officer in London.

6. Experiments • Rutherford- Gold Foil • Chadwick- Discovered Neutrons • Geiger- Worked with Rutherford • Marsden- Worked with Rutherford

7. EXPERIMENTS (CONT.) Rutherford

8. Experiments (CONT.) Chadwick

9. Experiments (CONT.) Geiger and Marsden worked with Rutherford

10. How does it fit in with the timeline? These were very basic experiments that gotthe ball rolling and it started people in the right direction.

11. Have these experiments held up? These experiments were the building blocks forthe experiments that are being conducted today.