Radium-226, a radium isotope, has a half-life (the time it takes half of the isotope to decay) of about 1620 years. A sample of radium-226 has a mass of 30 grams. Which of the following equations expresses the number of grams, g, of this sample that will be left after t years? A. g = 30 - 15(t / 1620) B. g = 30(1 / 2)^(t / 1620) C. g = 30 - 15^(t / 1620) D. g = 30(1 / 2)(t / 1620)
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So, after one half-life, half of the original substance will be left. After two half-lives, half of the remaining half will be left, and so on. This is an exponential decay process. The formula for exponential decay is: N = N0 * (1/2)^(t/h) where: N is the Show more…
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