In that particular Project Idea, radioactive decay of isotopes is modeled by rolling dice.While that procedure is a great way to grasp the concept, it would certainly be a time-consuming and tedious process in the real world, even with samples of only 100 dice, which could scarcely be called a "large number." Furthermore, how many trials of rolling up to 100 dice over and over again—while accurately keeping track of the results—would you be willing to do by hand?any hystricomorph rodent of the genus Dasyprocta, of Central and South America and the Caribbean : family Dasyproctidae.*Note: This is an abbreviated Project Idea, without notes to start your background research, a specific list of materials, or a procedure for how to do the experiment.The rule is that a sample is safe when its radioactivity has dropped below detection limits. So, if radioactive iodine-131 (which has a half-life of 8 days) is injected into the body to treat thyroid cancer, it’ll be “gone” in 10 half-lives, or 80 days.

Geologists, paleontologists, archeologists, and anthropologists use a statistical process like radioactive isotope decay to date objects through a method called radioactive dating (also known as radiometric dating).

Scientists know the half-life of C-14 (5,730 years), so they can figure out how long ago the organism died.

Carbon-14 dating can only be used to determine the age of something that was once alive.

Radioactive elements “decay” (that is, change into other elements) by “half lives.” If a half life is equal to one year, then one half of the radioactive element will have decayed in the first year after the mineral was formed; one half of the remainder will decay in the next year (leaving one-fourth remaining), and so forth.

The formula for the fraction remaining is one-half raised to the power given by the number of years divided by the half-life (in other words raised to a power equal to the number of half-lives).

As long as an organism is alive, the amount of C-14 in its cellular structure remains constant.

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