What is half-life in the context of radioactive decay?

Half-life is the time taken for half of the radioactive nuclei in a sample to decay.

Radioactive decay is a random process that occurs in unstable atomic nuclei. The half-life of a radioactive substance is the time taken for half of the original number of radioactive nuclei to decay. This is a characteristic property of the substance and is independent of the initial number of nuclei present.

The half-life of a substance can be used to predict how much of the substance will remain after a certain period of time. For example, if the half-life of a substance is one hour, then after two hours, only a quarter of the original amount of substance will remain.

The concept of half-life is important in many areas of science, including medicine, geology, and archaeology. In medicine, the half-life of a drug is used to determine the dosage and frequency of administration. In geology, the half-life of radioactive isotopes is used to date rocks and minerals. In archaeology, the half-life of carbon-14 is used to determine the age of organic materials.

Overall, understanding the concept of half-life is essential for understanding the behaviour of radioactive substances and their applications in various fields.