what is carbon 14

Carbon-14, also known as radiocarbon, is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons. It is present in trace amounts in the atmosphere, making up about 1 or 1.5 atoms per 10^12 atoms of carbon. Carbon-14 has a half-life of 5,730±30 years and decays into nitrogen-14. Carbon-14 dating is a scientific method that uses the decay of carbon-14 to determine the age of organic materials as old as approximately 60,000 years. Living organisms absorb carbon-14 into their tissue, and when they die, the carbon-14 starts to change into other atoms over time. Scientists can estimate how long the organism has been dead by counting the remaining carbon-14 atoms. Carbon-14 dating has been used for historical studies, atmospheric science, and archaeology. Carbon-14 is also used in chemical and biological research, in a technique called carbon labeling, where carbon-14 atoms can be used to replace nonradioactive carbon to trace chemical and biochemical reactions involving carbon atoms from any given organic compound. Carbon-14 is continuously formed in nature through an interaction of cosmic rays and nitrogen atoms. Carbon-14 has also been used in forensic science to determine the year of birth or death of an organism by comparing tissue carbon-14 levels to levels in a rapidly changing atmosphere.