Question

what do you mean radioactivity element​

Answer 1

Radioactive elements are made up of atoms whose nuclei are unstable and give off atomic radiation as part of a process of attaining stability. The emission of radiation transforms radioactive atoms into another chemical element, which may be stable or may be radioactive such that it undergoes further decay.

Answer 2

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A radioactive element is a fundamental element whose atomic nuclei demonstrates the phenomenon of radioactivity. The name ‘radioactive’ may suggest to you that radioactive elements radiate radio waves, but unfortunately that is not so! The name ‘radioactivity’ is a misnomer because these elements have nothing to do with radio waves!