What is a half-life?
the amount of time it takes for half of a radioactive substance to decay the amount of time it takes for all of a radioactive substance to decay
half the time it takes for a radioactive substance to break down
the reactive half of a radioactive substance

A half life is the amount of time it takes for half of a radioactive substance to decay.

Explanation:

Radioactive isotopes are defined as the isotopes which undergo decay processes very easily. They have very short half life. They are usually the isotopes of heavier elements.

Half life is defined as the time taken for the unstable isotope to fall to half its original value. It is designated as

All the radioactive reactions follows first order kinetics.

The equation used to calculate half life for first order kinetics:

where,

k = rate constant for first order kinetics

Hence, a half life is the amount of time it takes for half of a radioactive substance to decay.

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explanation:

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