Group Members___________________________________________________________________ ________________________________________________________________________________
Radioactive Decay Lab
1) The pennies represent the atoms in a sample of your radioactive isotope. 2) Seal the container and turn it 4-6 times. This represents one half-life of your radioactive isotope. 3) Spread the pennies out on the table. Remove all the pennies that are tails. 4) Count the number of remaining pennies (heads) and record the number in the data table. 5) Put the remaining pennies that were heads back into the container and repeat the steps until your data table is full.
Half-life Pennies period remaining (heads) removed (tails)
0 100 0
On graph paper provided, graph pennies vs time period. Plot all data and connect them with the best fit line.
1) Francium 220 has a half-life of 27.5 seconds. How much time will elapse after 4 half-life periods?
2) If you have 1600 Francium-220 atoms now, how many will you have left after 82.5 seconds?
3) What does the shaking of the pennies represent in terms of radioactive decay?
4) What do the pennies that were tails in the lab represent?
5) Carbon 14 has been used in a process called carbon dating to figure out the age of things,
why do you think carbon 14 is useful for that? Do you think it has a half-life that is a few seconds, days, years, decades or more?