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Learner Objective Learner will be able to calculate the half-life time for a radioactive isotope. Lec: Calculating Half-Life.
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Learner ObjectiveLearner will be able to calculate the half-life time for a radioactive isotope Lec: Calculating Half-Life
Half-Life: The time it takes for a radioactive isotope total mass to decay by one half. A half-life can be anywhere from fractions of a second to millions of years. Example: U238 has a half-life over 4.5 billion years and Po214 is 0.0000016 second.
The half-life of Ra222 at the end of 0 half life. 100% still radioactive radon.
The half-life of Ra222 at the end of 1st half life. 50% still radioactive radon.
The half-life of Ra222 at the end of 2nd half life. 25% still radioactive radon.
The half-life of Ra222 at the end of 3rd half life. 12.5% still radioactive radon.
The half-life of Ra222 at the end of 4th half life. 6.25% is still radioactive radon.
Calculating the half-life of Ra222. Ra222 has a half-life of 4 days and starting mass of 800g.
Bismuth, Bi214 has a half-life of 20 minutes, how much will still be radioactive when it reaches its 4th half-life and when will this occur? The starting radioactive mass is 200g.