Half life of Ba-137m.

Typed activity

Define "Radioactive half-life"

Include a screenshot of background counts. Find the background CPM. Note, radioactive counts can only be integer values.

Include a screen shot of your CPM data and the graph of counts vs. time.

Analysis:

1.Download and print this file.

2. Find the 1/2 life of Ba-137 using the graph, You may be able to note how you found the half-life on the graph using a colored pencil.

3. Make a statement that describes your thought process for finding the half-life of Ba-137.

4. To find the half-life of Ba-137 by developing a mathematical model,..

Radioactive decay follows a natural exponent curve, R = R_o e^-λt

R is the count at an elapsed time; time "t" in the formula

R_o is original activity count

λ is the decay constant for the isotope

t is the elapsed time

Half-life = ln(2) / λ
λ from your data is 0.2677
What is the half-life based upon the mathematical model? Show all work.

3. How many half-life's occurred during your Ba-137 decay data collection period?

3a. Support your answer

Questions:

A. Your teacher is going to toss the sample down the sink in the lab,... What do you think of this disposal method and why?

B. Possible sources of error? Hint: think about the data collection process,..

C. In what ways do you think a short lived radio-isotope may be used by society?