a.) initial sample left : 794g
b.) Time taken to decay : 3.39
Isotopes(200g) are atoms that have the same number of protons in their nucleus, but a different number of neutrons. This means that they have the same atomic number, but a different atomic mass. Because of this, isotopes have different physical and chemical properties. Isotopes can be stable, meaning that they do not undergo radioactive decay, or they can be unstable, meaning that they will undergo radioactive decay over time.
a.)
Substituting 25 for t in the expression, we get:
A(25)=
Thus, after 25 years, there will be =2003.97=>794 g of the initial sample left in the sample.
794
b.)
We want to find t such that A(t)=
=100.
Solving for t, we get:
=*t
=100
Dividing both sides by 200 and applying the natural logarithm to both sides, we get:
0.0541*t=ln(0.5)
Therefore, t=
=3.39 years.
To Learn More about Isotopes Decay follow link : brainly.com/question/16355768
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