Adecay chain

when the daughter nucleus produced in a radioactive decay is itself unstable, it will eventually decay and form its own daughter nucleus. if the newly formed daughter nucleus is also unstable, another decay will occur, and the process will continue until a nonradioactive nucleus is formed. such a series of radioactive decays is called a decay chain.

a good example of a decay chain is provided by 232 90th, a naturally occurring isotope of thorium.

what is the energy q released in the first step of the thorium-232 decay chain? the atomic mass of 232 90th is 232.038054 u and the atomic mass of 228 88ra is 228.0301069 u.