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How is a radioactive isotope’s half-life related to its decay constant?

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The decay constant (λ) and the half-life (T1/2) of a radioactive isotope are inversely related, representing the rate at which a population of unstable nuclei decays over time.12

Mathematically, this relationship is expressed as:
T1/2=ln(2)λ≈0.693λ

In this context, the decay constant λ represents the proportionality between the size of a radioactive population and its rate of decrease, while the half-life is the specific time interval required for that population to reduce by half. Because radioactive decay is a statistical exponential process, these two values provide equivalent ways to describe the stability and transition rate of a given nuclide.123