CHEM131: Nuclear Chemistry (Part 4)

Introduction to Artificial Radioactivity and Bombardment00:00:00

The video begins by reviewing that while only about 250 nuclides are stable, thousands are radioactive, occurring either naturally or synthetically. It introduces artificial radioactivity and explains that synthetic radioisotopes are created via bombardment reactions, where stable nuclei are hit with particles like neutrons or alpha particles using particle accelerators to overcome electrostatic repulsion.

Historical Nuclear Transmutations00:02:00

This section details Ernest Rutherford's 1919 experiment where he bombarded nitrogen-14 with alpha particles to produce oxygen-17 and a proton. It then discusses the first artificial radioactive isotope created by Irene Curie and Frederic Joliot in 1934, using aluminum-27 and alpha particles to create radioactive phosphorous-30.

Transuranium Elements and Superheavy Synthesis00:04:00

The discussion moves to transuranium elements like neptunium and plutonium, produced by bombarding uranium-238 with neutrons. It also mentions the 1996 synthesis of element 112 (Copernicium) by European scientists who bombarded a lead target with zinc atoms for three weeks.

Applications of Radioactivity in Medicine and Industry00:05:10

The final part highlights the beneficial uses of radioactivity, including cancer therapy using Cobalt-60 gamma rays and thyroid treatment using Iodine-131. It lists various diagnostic isotopes such as Carbon-11 for brain scans and Sodium-24 for circulatory disorders, and mentions industrial uses like Americium-241 in smoke detectors and gamma rays for killing parasites in food.