Some isotopes are unstable, or radioactive, meaning they will decay over time and turn into another isotope or stable element. In the interactive simulation, participants manipulate elements to create isotopes and gather information....

Are all atoms of an element the same? How can you tell one isotope from another? Use the sim to learn about isotopes and how abundance relates to the average atomic mass of an element.

[Free Registration/Login Required] Students explore how percent abundances of different isotopes affect the average atomic mass for that given element. Students form connections between the average atomic mass and a person's body mass....