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Half life problem as follows at 80 min 45 percent of original amount remains What is the half life of the substance showing all work?
Wiki User
∙ 14y ago
Half life is the time for one half of a radioactive substance to decay. In the second half life, another half decays, leaving one quarter. In the third half life, another dalf decays, leaving one eights. And so on and so forth...
The equation for the amount left after N half lives is...
AN = A0 2(-N/H)
...where H is the half life.
In the question asked, if 0.45 of a substance remains after 80 minutes, what is the half life, simply plug in the observations and solve...
0.45 = 2(-80/H)
log2(0.45) = log2(2(-80/H))
-1.152 = -80/H
H = 69.44 minutes
Wiki User
∙ 14y ago
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