Decay product

{ "text": Some tiny things change over time.

They turn into new, smaller things. These new things are left behind. This helps us learn about our world. It is like a slow chain. Can you imagine tiny things changing?

", "media": [ "File:Stylised atom with three Bohr model orbits and stylised nucleus.svg", "File:Thorium decay chain from lead-212 to lead-208.svg" ] }