Students will also consider the future of nuclear energy. Since the dropping of atomic bombs at the end of World War II, no other potential energy source has been more controversial. For many, the use of "atomic" power conjures up bombs and nuclear disaster. Still some people advocate this as clean energy. However, there are problems with disposing of nuclear waste, and just who wants to have a nuclear power plant in their back yard? There is much here for students to consider. What are the pros and cons of this power source? We would need to consider the problems that have occurred like Three Mile Island, and Chernobyl. Students will be presented with the usefulness of nuclear, as well as, the potential for devastating accidents that could cause irreparable damage.
Nuclear power depends upon the chain reaction or fission of the uranium atoms. In this process, some neutrons that form the nucleus of a uranium nucleus fly off when it splits (fission) and hit other nuclei. This causes them to split in two releasing more energy and two more neutrons. They in turn will fly off and hit another nuclei splitting that and releasing more energy and two more neutrons. This chain reaction can build up to a dangerous level so rods are inserted in the middle of a nuclear reactor to slow down the reaction. In theory, this nuclear reaction does not have the potential to cause a nuclear explosion. However, there is the potential of danger from nuclear waste, and radioactive materials released unexpectedly from the reactors. Nuclear waste emits harmful radiation over a long period of time. It does not just meld back into the environment.
Activity 7 Nuclear Chain Reaction
The YouTube has quite a few film clips of a demonstration replicating what happens in fission or a chain reaction. The film shows a number of mouse traps in a large closed plastic container. Each mouse trap has a ping pong or tennis ball on it. An extra ball is thrown into the container and immediately hits a trap which sends another ball into the air. The traps keep snapping and the balls keep flying until most have been tripped.
Fission is the process of breaking up the atom but scientists are intrigued with the idea of nuclear fusion which is the connecting of the nuclei of hydrogen atoms. This would require a smaller amount of material and potentially result in the release of more energy than the fission reaction. Fusion, as it is called, is the connecting of two nuclei. It is the basic reaction that is occurring continually on the sun. This reaction is hard to produce and harder to control.