💏intro to chemistry review

key term - Half-life

Definition

Half-life is the time required for half of the radioactive nuclei in a sample to decay. It is a characteristic property of each radioactive isotope.

5 Must Know Facts For Your Next Test

  1. The half-life of a radioactive isotope is constant and does not depend on the initial amount or external conditions.
  2. The formula to calculate the remaining quantity of a substance after n half-lives is $N = N_0 \times (\frac{1}{2})^n$ where $N_0$ is the initial quantity.
  3. Commonly used isotopes with known half-lives include Carbon-14 (5730 years) and Uranium-238 (4.5 billion years).
  4. Half-life can be used in radiometric dating to determine the age of archaeological finds.
  5. A shorter half-life means quicker decay, while a longer half-life indicates slower decay.

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