Fission Lise Meitner- Austrian physicist during time of WWII. Discovered that bombardment of uranium with neutrons can split the nucleus into two pieces. Fission- (“splitting”) the splitting of an atomic nucleus into two or more large fragments.

Fission of one nucleus often leads to fission of another nucleus, since neutrons are emitted in the process. Thus nuclear reactions are often chain reactions. If rate of reaction is controlled, this energy can be used to heat materials and do useful work. Fission

Nuclear Fusion- When two or more nuclei combine to form a larger nucleus. This is the nuclear process which produces energy in stars ( ex: the sun ). Most typical solar reaction: 2 hydrogen nuclei fuse to form helium. This is the energy source that sustains life on earth.

Fusion reaction: There are 2 isotopes normally involved in hydrogen fusion: Deuterium (mass =2) and tritium (mass=3) What is the nuclear notation for these 2 isotopes?

Some advantages in utilizing fusion reactions: 1.The fusion of hydrogen produces 20 times the energy produced by the fission of an equal mass of uranium. 2.Deuterium is abundant on earth. 3.No radioactive products produced. 4.Reactions are easier to control than fission reactions.

Problems with Fusion Reactions: Enormous pressures and temperatures are required for the reaction to take place (on Earth, a temperature of 200 billion Kelvin). There aren’t any materials that would contain this type of reaction.