Part A:
Tritium is a radioactive isotope of the element hydrogen. Tritium has a half-life of 12.5 years.
How many years would it take until only 3.22% of a sample remain?
Answer should be in years.
Part B:
Radioactive Carbon-11 has a half life of only 20.3 minutes and an atomic mass number of 11 u.
Calculate the activity of 3.58 g of Carbon-11.
Answer should be in Bq.
A) Decay constant = 0.693 / t
where t= half life
= 0.693 / 12.5
= 0.05544 year^-1
N = No*e^-t
0.0322No = No*e^-0.05544*t
t = 61.97 years
B ) activity = N
= (0.693/20.3) * (3.58)
= 0.122 Bq
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