How are the terms "activity" and "becquerel" related?
A radioactive isotope source has a mass of 120 g. If the isotope has a half life of 20 secs what would be the mass of the isotope in 2 mins?
k = 0.693/t1/2
Substitute k into the equation below.
ln(No/N) = kt
No = 120
N = ?
k from above
t = 120 seconds (since the half life is given in sec you will have a seconds terms for k so you must convert 2 minutes to seconds).
Solve for N.
See the link below for the definition of Bq.
http://en.wikipedia.org/wiki/Becquerel
The terms "activity" and "becquerel" are related in the context of radioactivity. Activity refers to the rate at which a radioactive material undergoes radioactive decay. It is measured in terms of the number of radioactive decays occurring per second. Becquerel (Bq) is the unit used to measure activity in the International System of Units (SI). One becquerel represents one decay per second.
To calculate the mass of the isotope after a given time, we can use the concept of half-life. The half-life of a radioactive isotope is the time it takes for half of the initial quantity of the isotope to decay.
Now, let's calculate the mass of the isotope in 2 minutes (120 seconds), given that its half-life is 20 seconds and its initial mass is 120 grams.
First, we need to determine the number of half-lives that have occurred during the 2-minute period. We divide the total time (120 seconds) by the half-life (20 seconds), which gives us:
Number of half-lives = Total time / Half-life = 120 s / 20 s = 6 half-lives
Since each half-life reduces the mass to half, after 6 half-lives, the remaining mass will be:
Remaining mass = Initial mass / (2^(Number of half-lives))
Remaining mass = 120 g / (2^6) = 120 g / 64 = 1.875 g
Therefore, the mass of the isotope after 2 minutes would be approximately 1.875 grams.