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Objective: describe how radioactive isotopes are useful. What are the three types of radioactive decay?. DO NOW. Determining the age of natural materials on Earth Tracing the steps of chemical reactions and industrial processes Diagnosing and treating diseases Providing sources of energy.
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Objective: describe how radioactive isotopes are useful. What are the three types of radioactive decay? DO NOW
Determining the age of natural materials on Earth Tracing the steps of chemical reactions and industrial processes Diagnosing and treating diseases Providing sources of energy Using Radioactive Isotopes
When atoms decay, they change into other kinds of atoms but it does not all disappear at once. The atoms decay randomly, one at a time. The time it takes for one atom to decay to half its size can be measured. The HALF-LIFE of an isotope is the length of time it takes for half of the atoms of the sample to decay. Radioactive Dating
Fossils are the trace remains of living things that have been preserved. Scientists use half-lives of some elements to date the fossils. Process is called radioactive dating. Example, plants use carbon dioxide and if a plant is preserved after it dies, the amount of Carbon-14 present can tell us how long ago the plant died. Fossils
Tracers are radioactive isotopes that can be followed through the steps of a chemical reaction or industrial process. Scientists will put radioactive isotopes into the water and then water a plant. They will be able to follow the radioactive phosphorous through the plant and see how it is used in the plant. Use in Science and Industry
Detect medical problems and treat some diseases. Tracers are injected into the body travel to organs and other structures where the chemical is normally used. Radiation is used to treat cancer cells from outside the body. Uses in Medicine
Some power plants use radioactive isotopes as fuel. Nuclei of radioactive isotopes are made to split into smaller fragments and they release a large amount of energy. Nuclear Power
Objective: describe how radioactive isotopes are useful. What are some uses for radioactive isotopes? HOMEWORK: pg 150 #11-19 Recap
Create a table that looks like this in your notes. Half-Life Activity
With a partner, take a bag of paper squares (there are 100) Shake the bag for 20 seconds and then dump the bag onto the desk. Remove all the papers that are white side up. Record the information needed in your table. Repeat steps putting only papers with color side up back in the bag until you have 2 left on the desk. Half-Life Activity