Radioactive DecayA series of reactions that starts with an unstable

nucleus and results in a stable nucleus

Transmutation- the conversion of one element into another element

Radiation LifespanHalf-life: time necessary for half of a mass of a

radioactive element (parent) to decay to a stable nonradioactive (daughter) product

http://www.pbs.org/wgbh/nova/tech/radiocarbon-dating.html

Practice Half-Life

Iron-59 is used in medicine to diagnose blood circulation disorders. The half-life of iron-59 is 44.5 days. How much of a 2.0 mg sample will remain after 133.5 days?

After 250 years, 0.500 g of a radioisotope remains from a sample that had an original mass of 2.000 g. What is the element’s half-life?

How much of the original sample remains after 1,000 years?