These excited neutrons then collide with nitrogen atoms in the atmosphere, changing them into radioactive carbon-14 atoms.
CARBON-14 IS ABSORBED (Figure 1b): Plants absorb this carbon-14 during photosynthesis.
Although many people think radiocarbon dating is used to date rocks, it is limited to dating things that contain the element carbon and were once alive (like fossils).
When the organisms die, they stop incorporating new C-14, and the old C-14 starts to decay back into N-14 by emitting beta particles.Familiar to us as the black substance in charred wood, as diamonds, and the graphite in “lead” pencils, carbon comes in several forms, or isotopes.One rare form has atoms that are 14 times as heavy as hydrogen atoms: carbon-14, or C ratio gets smaller.It cannot be applied to inorganic material such as stone tools or ceramic pottery.The technique is based on measuring the ratio of two isotopes of carbon.Thus carbon-14 has six protons and eight neutrons.) Carbon-12 is by far the most abundant carbon isotope, and carbon-12 and -13 are both stable.