Module 11 Flashcards
Identify the different types of radiation and the properties of each type.
Radioactivity is the spontaneous emission of radiation from the nucleus of an unstable atom. The three major kinds of radiation are called alpha 1a2, beta 1b2, and gamma 1g2. Alpha radiation consists of helium nuclei, small particles containing 2 protons and 2 neutrons 14
2He2; b radiation consists of electrons 1 0 -1e2; and g radiation con-sists of high-energy light waves. Every element in the periodic table has at least one radioactive isotope, or radioisotope
Identify natural isotopes, and distinguish between stable and unstable isotopes
Natural isotopes are those that occur naturally in the environment, as opposed to artificially created isotopes.
Stable Isotopes: These isotopes do not decay over time. They are non-radioactive and remain constant in nature.
Unstable Isotopes: These are radioactive isotopes that decay over time, emitting radiation in the form of alpha, beta, or gamma particles.
Identify the types of ionizing radiation
High-energy radiation of all types—a particles, b particles, g rays, and X rays—is called ionizing radiation. When any of these kinds of radiation strikes an atom, it dislodges an orbital electron and gives a reactive ion that can be lethal to living cells.
Gamma rays and X rays are the most penetrating and most harmful types of external radiation; a and b particles are the most dangerous types of internal radiation because of their high energy and the resulting damage to surrounding tissue.
Radiation intensity (I) decreases with the square of the distance from the source
Identify methods for detecting radiation and the units used to measure radiation exposure.
The curie (CI) measures the number of radioactive disintegrations per second in a sample; the roentgen (R) measures the ionizing ability of radia-tion. The rad measures the amount of radiation energy absorbed per gram of tissue; and the rem measures the amount of tissue damage caused by radiation.
Radiation effects on human exposure, when is it noticeable and when is it lethal?
Radiation effects become noticeable with a human exposure of 25 rem and become lethal at an exposure above 600 rem
Define Transmutation
Transmutation is the change of one element into another brought about by a nuclear reaction. Most known radioisotopes do not occur naturally but are made by bombardment of an atom with a high-energy particle. In the ensuing collision between particle and atom, a nuclear change occurs and a new element is produced by artificial transmuta-tion
What are the decay modes?
- Alpha (4/2He): atomic mass and atomic number decrease.
- Beta ( or 0/-1e): atomic mass constant; atomic number increases.
β -1 - Positron (0e): atomic mass constant; atomic number decreases.
1 - Gamma (): energy released; no change in atomic mass or number.
Define Nuclear Fission
A heavy nuclei split into lighter nuclei
