What is the definition of the half-life of a radioactive isotope? A. The time it takes for half the parent nuclei in a sample to become
daughter nuclei
B. The time it takes for all the parent nuclei in a sample to become
daughter nuclei
C. The time it takes for all the daughter nuclei in a sarnple to become
parent nuclei
D. The time it takes for half the daughter nuclei in a sample to
become parent nuclei

Half-life is the amount of time it takes for the initial mass of the isotope to decompose, by half, into other lighter atoms.

Explanation:Different radioactive isotopes have different half-lives. For example, the element technetium-99m has a half life of 6 hours. This means that is 100 kg of the element is left to decay, in 6 hours, 50kg of the mass will have changed into other elements/atoms. The half-life of uranium-238 is 4.5 billion years while that of polonium-216 is only 0.145 seconds.

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frequency or wavelenth of em radiation in a vacuum