1 Divide the amount of the substance at one point in time by the amount remaining after a period of time. The formula for calculating half life is as follows: t 1/2 = t * ln(2)/ln
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1. Suppose you know the proportions of a substance at two points in time. Denote the difference between these two points in time with the letter "T. Denote the ratio of the smaller
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Check the time between your first decay rate and when the decay rate reaches half this number.
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You seem to have time and initial mass (or radioactivity) data from two trials, which is okay. But you need the final values to find the halflife. (Half life is the time needed to
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