Final answer:
Radioactive dating uses the decay of isotopes, such as carbon-14 and uranium-238, to estimate the age of various materials by understanding their half-lives. The half-life is the period needed for half of a radioactive substance to decay, and by measuring the parent-to-daughter isotope ratio, scientists can calculate the time that has passed since the organism died or the rock formed.
Step-by-step explanation:
Understanding Radioactive Dating in Nuclear Chemistry
Radioactive dating is a technique in nuclear chemistry utilized to estimate the age of materials such as rocks, minerals, fossils, and even archaeological artifacts. This method exploits the predictable decay rates of radioactive isotopes, known as their half-lives. The half-life represents the time required for half of a given quantity of an isotope to undergo radioactive decay. By measuring the ratio of parent isotopes (original radioactive substances) to daughter isotopes (the products of decay), geologists can calculate the number of half-lives that have elapsed. This, in turn, allows them to determine the material's age with remarkable precision.
For instance, carbon-14 (14C), which has a half-life of approximately 5,730 years, is widely used to date organic material—such as wood or bone—up to about 50,000 - 60,000 years old. When a living organism dies, it no longer takes in 14C, and the ratio between 14C and non-radioactive carbon isotopes begins to decrease. By measuring this ratio in comparison to that in a contemporary sample, scientists can estimate the time elapsed since the organism's death. The precision of carbon-14 dating has been enhanced by calibration with other dating methods, such as dendrochronology (tree ring dating).
While carbon-14 is optimal for dating relatively young organic artifacts, radioactive dating can also employ isotopes like uranium-238 (U-238) for dating geologic materials with a much longer history. With a half-life of 4.5 billion years, U-238 allows scientists to reach back in time to date the age of the Earth and other ancient geological formations.