Nuclear Chemistry Aim Nuke1 What is radioactivity?

A Brief History of Nuclear Chem Wilhelm Roentgen – German discovered “X-rays”, a powerful form of electromagnetic energy Henri Becquerel - French discovered radioactivity when he left uranium on top of photographic film also suffered radiation burns from a sample of radium in his pocket

A Brief History of Nuclear Chem Henri and Marie Curie – French using radiometry (the measure of electromagnetic energy strength and distribution) separated uranium ore into different fractions Discovered thorium, polonium (named for Poland, where Marie was originally from) and radium

A Brief History of Nuclear Chem Ernst Rutherford - English showed that radioactive decay can be described by a simple equation implying that a given radioactive substance has a characteristic "half-life" the TIME taken for HALF THE AMOUNT of radioactivity present in a source to decay He also coined the terms alpha particle, beta particle, and gamma rays he converted nitrogen into oxygen (first example of artificial transmutation) Theorized there were particles called neutrons

A Brief History of Nuclear Chem 1932 James Chadwick Discovers Rutherford’s neutrons through experimentation He shot alpha particles through a beryllium sheet, and through a layer of wax Detected protons at the end of the process

A Brief History of Nuclear Chem 1938 Otto Hahn, Lise Meitner, and Fritz Strassmann became the first to split uranium atoms by bombarding them with neutrons Measureable amounts of energy released Coined the name fission, after binary fission in biology Small nuclear reaction!

A Brief History of Nuclear Chem 1939 Leo Szilard Writes a letter with fellow scientists to President Franklin D. Roosevelt Warns of the potential of fission as a potentially devastating weapon Nazis in Germany were working already working on developing it Albert Einstein signs the letter to add his support Result Roosevelt authorizes a small study into uranium. US, UK, and Canada begin work on the atomic bomb

A Brief History of Nuclear Chem 1942 Enrico Fermi successfully created the first man-made nuclear chain reaction Squash court under the stadium at the University of Chicago Also almost created the first nuclear meltdown On that same squash court Meltdown the nuclear material inside the reactor overheats Melts through building Heads toward China Also called the “China Syndrome”

A Brief History of Nuclear Chem The Manhattan Project a research and development project that produced the first atomic bombs during World War II. July 16 th, 1945 Trinity Test at Los Alamos First nuclear bomb test Upon seeing the destructive power of the atomic bomb, Robert Oppenheimer, project leader, quotes the Bhagavad Gita, a Hindu text, saying: “Now I am become death, the destroyer of worlds”

A Brief History of Nuclear Chem August 6 th, 1945 a uranium bomb, Little Boy, dropped on Hiroshima Japan August 9 th, a plutonium bomb, Fat Man, dropped on Nagasaki, Japan on The cities are devastated, with up to 250,000 people dead. Japan surrenders unconditionally 6 days later, on August 15th, Use of the atomic bombs ends World War II US does not have to invade Japan, saving millions of lives both Japanese and Allied Controversy still surrounds the decision to use the weapon even till today