What is the definition of half-life in the context of radioactive isotopes?

The correct definition of half-life in the context of radioactive isotopes is the time required for half of the radioactive atoms in a sample to decay. This measurement is crucial for understanding how quickly a radioactive isotope loses its radioactivity and transforms into a more stable form or a different element altogether.

Half-life is a characteristic property of each radioactive isotope, allowing scientists to predict the behavior of that isotope over time. For example, if a specific isotope has a half-life of 10 years, after that period, only half of the original amount of the isotope will remain radioactive; the other half will have decayed into other elements or isotopes. This concept is essential in fields such as nuclear medicine, archaeology (carbon dating), and nuclear physics, as it helps determine the age of materials and the safety measures necessary when handling radioactive materials.

The other options do not encapsulate the scientific definition of half-life. While they may reference aspects of radioactivity or safety regarding radioactive materials, they do not correctly convey the concept of half-life itself, which is fundamentally about the decay rate of radioactive atoms in a sample.