What do the following terms mean? Radiation Radioactivity Fusion Fission S-79 Students will distinguish the characteristics and components of radioactivity.

SPS3 Students will distinguish the characteristics and components of radioactivity. a.Differentiate among alpha and beta particles and gamma radiation. b.Differentiate between fission and fusion. c.Explain the process of half-life as related to radioactive decay. d.Describe nuclear energy, its practical application as an alternative energy source, and its potential problems Chapter 10 Nuclear Chemistry

What happens during nuclear decay? What are three types of nuclear radiation? How does nuclear radiation affect people? 10.1 Radioactivity

Antoine Henri Becquerel – French physicist –Accidentally discovers that Uranium left next to photographic plates will cause them to become cloudy –Uranium must be emitting some ray that exposed the film –Radioactivity – an unstable atom emits particles and energy 10.1 Radioactivity What happens during nuclear decay?

Radioisotope – any atom that has an unstable nucleus (radioactive isotope) –Written with the name of the element and the mass number (total of protons and neutrons) –Uranium Radioactivity What happens during nuclear decay?

Nuclear Decay – atoms of one element change into atoms of another element –Uranium 238 decays to become thorium 234 Three common types of Nuclear Radiation –Alpha Decay –Beta Decay –Gamma Ray 10.1 Radioactivity What happens during nuclear decay?

Alpha Particle -  –Made of two protons and two neutrons –Postively charge –A Helium nucleus –The equation for the Alpha Decay of Uranium- 238 to Thorium-234 would be written as –Can be stopped by a sheet of paper 10.1 Radioactivity What are three types of nuclear radiation?

Beta Particle -  –Electron emitted from the nucleus (not from the electron cloud) –Negative charge –A neutron decays to a proton and an electron –Described by the equation –Mass stays the same, protons increase by 1 –Can be stopped by a thin sheet of metal 10.1 Radioactivity What happens during nuclear decay?

Gamma Ray -  –Electromagnetic ray emitted by decay –No charge, no mass, no change in nucleus –Energy of the nucleus decreases –Stopped by 5 cm of lead, or 2 m of concrete 10.1 Radioactivity What happens during nuclear decay?

Background Radiation – occurs naturally in the environment –Cosmic rays –Radioisotopes in the air, water, rocks, plants –Usually low and safe 10.1 Radioactivity How does nuclear radiation effect people?

Nuclear radiation ionize atoms –Breaks the bonds holding molecules together –DNA, RNA strands get changes –Alpha – skin damage (not serious unless inhaled or eaten) –Beta – damages body tissue – only surface –Gamma – damage body tissue – deep into body –Symptoms – hair falls out, skin sloughs off, vomiting, 10.1 Radioactivity How does nuclear radiation effect people?

What happens during nuclear decay? What are three types of nuclear radiation? How does nuclear radiation affect people? 10.1 Radioactivity