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Why use a term like half-life rather than lifetime? The answer can be found by examining Figure 1, which shows how the number of radioactive nuclei in a sample decreases with time. In this section we explore half-life and activity, the quantitative terms for lifetime and rate of decay. This means they have shorter lifetimes, producing a greater rate of decay. For example, radium and polonium, discovered by the Curies, decay faster than uranium.
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However, some nuclides decay faster than others. Calculate age of old objects by radioactive dating.By the end of this section, you will be able to:
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