1 : the time required for half of something to undergo a process: as a : the time required for half of the atoms of a radioactive substance to become disintegrated b : the time required for half the amount of a substance (as a drug or radioactive tracer) in or introduced into a living system or ecosystem to be eliminated or disintegrated by natural processes
2 : a period of usefulness or popularity preceding decline or obsolescence <slang usually has a short half-life>
2 : a period of usefulness or popularity preceding decline or obsolescence <slang usually has a short half-life>
For americium-241, it is known that half of the atoms decay in 458 years. Therefore, 458 years is the half-life of americium-241. Every radioactive element has a different half-life, ranging from fractions of a second to millions of years, depending on the specific isotope. For example, americium-243 has a half-life of 7,370 years.
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She's definetely a fan of the locomotion
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