B The process of emitting particles or energy waves from an unstable nucleus is called radioactive decay. C Scientists can predict when a nucleus will decay. D Radiation refers to particles or waves emitted by a decomposing nucleus. There are three main types of ionizing radiation emitted by the unstable nuclei of radioactive atoms: alpha, beta and gamma radiation.
Radiation can be used to kill bacteria and thus sterilize surgical equipment. Items can be sealed in airtight packaging before being irradiated, meaning there is no chance of them becoming contaminated again before use.