SOLUTION: a radioactive substance has a half life of 120 days.if an original sample of the substance has a mass of 10 grams, about how much of the substance will remain after 180 days of the

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Question 452384: a radioactive substance has a half life of 120 days.if an original sample of the substance has a mass of 10 grams, about how much of the substance will remain after 180 days of the original substance
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Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
a radioactive substance has a half life of 120 days.
if an original sample of the substance has a mass of 10 grams, about how much
of the substance will remain after 180 days of the original substance
:
The radioactive decay formula
A = Ao*2^(-t/h)
where
A = resulting amt after t time
Ao = initial amt
t = time
h = half-life of substance
:
A = 10*2^(-180/120)
A = 10*2^(-3/2)
:
Find 2^-1.5 on calc
A = 10 * .35355
A = 3.5355 grams after 180 days