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This quiz contains 6 questions from a mix of 1 subtopics.
What is the definition of the half-life (t21) of a radioactive isotope?
the time taken for all the unstable nuclei in a sample to decay
the time taken for a quarter of the unstable nuclei in a sample to decay
the time taken for half of the unstable nuclei in a sample to decay
the time taken for three-quarters of the unstable nuclei in a sample to decay
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Which of the following statements about half-life is true?
half-life is not related to the duration of radioactivity
longer half-lives indicate the isotope remains radioactive for shorter periods
longer half-lives indicate the isotope remains radioactive for longer periods
shorter half-lives mean slower decay
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How can the half-life (t21) be determined from exponential decay graphs?
by locating the point on the curve corresponding to half of the initial number of undecayed nuclei (N0)
by calculating the area under the decay curve
by noting the final number of undecayed nuclei when time t = infinity
by drawing a line from the origin to the point where the number of undecayed nuclei is zero
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What is the term for the time taken for half of the unstable nuclei in a sample to decay?
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Explain how the half-life of a radioactive isotope can be determined from an exponential decay graph.
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Explain why the decay of individual nuclei is unpredictable, but the overall decay rate for a large number of nuclei is predictable.
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