Be sure and record when the marked atom decays. Cover the original tray and flip the pennies. Also mark with an asterisk the flip number when the marked penny decayed. Construct a graph plotting flip number and percentage of atoms remaining. Plot a line of best fits using an exponential relationship and answer the following questions.
Scientists describe the stability of an isotope by reporting it's half-life.
Half-life is the amount of time required for one half of a radioactive sample to decay. The graph below shows the radioactive decay curve for the isotope thorium-234. Use the graph to answer these questions. Go to top .