ABSTRACT
Carbon has three isotopes in nature: 12C-common and stable; 13C-rare and stable; and 14C-very rare and radioactive. The heavy carbon isotope, 14C, is unstable and decays radioactively into 14N, emitting a beta (β −) particle that can be measured in specialized laboratories. The half-life of 14C is 5730 years. The above information can be summarized in the following way: The radioactive decay curve of 14C is given in Fig. 11.1. What fraction of an initial concentration of 14C is left after 10,000 years? The answer, read from Fig. 11.1, is 27%.
