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• In 1896, French physicist Henri Becquerel accidentally discovered radioactivity while investigating phosphorescence in uranium salts.
• The Curies and Henri Becquerel were awarded the Nobel Prize in physics for the discovery and exploration of natural radioactivity in 1903.
• Polonium was discovered by Marie and Pierre Curie in 1898.
• Radon is produced by the radioactive decay of radium.
• Radium's name comes from the Latin word “radius” meaning “ray.”
• Alpha particles are composed of two protons and two neutrons, two and two.
• When an atom undergoes alpha decay, it loses two protons and two neutrons to form an alpha particle (a helium-4 nucleus).
• The atom’s atomic number decreases by two, and its mass number decreases by four.
• Uranium-238 has 92 protons and 146 neutrons.
• When uranium-238 undergoes alpha decay, it loses two protons and two neutrons to produce an alpha particle and thorium-234.
• Radiation is composed of high-velocity electrons emitted from an unstable nucleus.
• Gamma radiation is stopped by solid materials.
• Nuclear reactions are changes that occur in the structure of atomic nuclei.
• Nuclear fission is a nuclear reaction that occurs when an atomic nucleus splits into two smaller parts.
• Uranium was first identified in pitchblende ore in 1789 and was named after the planet Uranus, which had been discovered around that time.
• Enrico Fermi was an Italian physicist most known for his work on beta decay, the development of the first nuclear reactor, and his contributions to the development of quantum theory.
• Plutonium was discovered in 1940 at the University of California at Berkeley.
• Nuclear changes are changes that occur in the structure of atomic nuclei.
• Nuclear reaction is a nuclear reaction that occurs when an atomic nucleus splits into two smaller parts.
• Uranium was first identified in pitchblende ore in 1789.
• Pitchblende was an Italian physicist most known for his work on beta decay, the development of the first nuclear reactor, and his contributions to the development of quantum theory.
• Enrico Fermi was a physicist known for his work on beta decay, the development of the first nuclear reactor, and his contributions to the development of quantum theory.
• Plutonium was discovered in 1940 at the University of California at Berkeley.
• California is the location where plutonium was discovered in 1940 at the University of California at Berkeley.