eli5: What’s the half life of an element?

Question

What do people mean when they say “half life of element X”?

In: 0

Answer 1

Half life is the time taken for half of the radioactive nuclei to decay. Radioactive atoms decay due to their unstable nuclei and create another element.

Because of Quantum Physics, we can’t determine with certainty when one atom decays, however, with a large enough sample, we can estimate the amount of time taken for half of an elemental isotope becomes a different element.