SOLUTION: The half-life of plutonium-241 is approximately 13 years.
a. How much of a sample weighing 3 g will remain after 80 years?
b. How much time is necessary for a sample weighing 3 g
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-> SOLUTION: The half-life of plutonium-241 is approximately 13 years.
a. How much of a sample weighing 3 g will remain after 80 years?
b. How much time is necessary for a sample weighing 3 g
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Question 1017011: The half-life of plutonium-241 is approximately 13 years.
a. How much of a sample weighing 3 g will remain after 80 years?
b. How much time is necessary for a sample weighing 3 g to decay to 0.1g? Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! P=pexp(-kt)
0.5=exp(-kt)
ln of both sides
ln2=-13k
k=1n2/13=0.0533
Now use that for time=80 years; it is 6 half lives, so I would expect about 1% to be left.
P=3*exp(-0.0533*80)=3 exp(-4.26558)=3*0.014=0.042 gm, which is about 1%.
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To decay to 0.1 gm
This should take less time.
it is 1/30th of the original amount
ln(1/30)=-3.401
That equals -0.0533t
63.8 years.
Can also do it by
ln0.1=3exp(-0.0533t)
and take logs of both sides.
