Radioactivity

This week, we learned about radioactivity. It's when atoms decay because they become unstable into another stable element. This can be caused by a different number of neutrons, or when high energy particles slam into an atom and destabilize it. The most common kind of radiation is alpha particle decay, where decaying elements spit out alpha particles (4/2 Helium atoms) and lose 4 in mass number and 2 in atomic number. Beta decay is where it loses a beta particle (electron) and loses only 1 in atomic number.

Sometimes, radioactive decay can result in gamma ray production, which are just high energy particles with no weight and no charge. Light is an example of a gamma ray.

These radioactive atoms all have half-lives, which is the amount of time required for the sample to lose 50%. Carbon-14 has a half-life of around 5730 years, while Uranium-238 has a half life of 4.46 [b]billion[/b] years! Scientists and archaeologists can use these half-lives to date ancient artifacts and samples of matter.