During nuclear fission, neutron particles hit the atoms in Uranium-235, splitting them apart and releasing large amounts of heat and radiation. More neutrons hit more atoms, repeating the process and creating a chain reaction that occurs in the nuclear core reactor. The heat released from the reaction is used to power the same type of steam generator used in natural gas and coal power plants. A simple project to demonstrate a chain reaction requires attaching ping pong balls to mouse traps, strung together with string. Place a plexiglass containment box over all the traps; pull the string and watch the balls hit each other, simulating neutrons hitting atoms successively.
Uranium is mined and processed, in similar fashion as other metals, except the byproduct, mill tailings is radioactive. Each ton of uranium ore yields one to four pounds of concentrate, called "yellow cake. Mining uranium creates large amounts of low-level radioactive wastes, the decay of which, produces radon, a radioactive gas. For this reason, mill tailings must be covered with clay, soil and rocks to prevent radon from escaping. Uranium is a naturally occurring substance and found in soils in many western states at relatively safe levels; however, soil disturbance during basement construction can release unsafe levels of radon gas. Radon detectors can be bought at home improvement stores. A student analysis of radon detectors can demonstrate the natural decay process of uranium.
Exposure to uranium is most likely if you live near a mining facility or a nuclear weapons facility. You can be exposed to uranium through inhalation of dust or by ingesting contaminated food and water. After ingestion, 99 percent of the uranium leaves the body through feces or urine, damaging the kidneys. The remaining uranium can be deposited into bones and can lead to cancer. There are special lab tests that can measure the amount of uranium in human waste to determine levels of exposure. Contacting a laboratory for more information on special tests to get more information on uranium analysis is a worthwhile project for kids.
Uranium ore can be handled with gloves to protect handlers from any low-level radioactive effects. Avoiding inhalation or ingestion of high levels of radioactive isotopes is the only way to protect against toxicity. One health benefit to uranium is the use of low-level radioactive isotopes in nuclear medicine to diagnose and treat illnesses, such as thyroid cancer, blood disorders and certain bone pain from other types of cancer. Dosimeters are used to measure exposure to hazardous contaminants, including radioactive contaminants. A description of how dosimeters work is a good project for kids to demonstrate how exposure is measured.