The longest-lived radioisotope is 14C, with a half-life of 5,730 years. This is also the only carbon radioisotope found in nature—trace quantities are formed cosmogenically by the reaction 14N + 1n → 14C + 1H.

Which is the most radioactive carbon?

carbon-14 carbon-14, the longest-lived radioactive isotope of carbon, whose decay allows the accurate dating of archaeological artifacts. The carbon-14 nucleus has six protons and eight neutrons, for an atomic mass of 14.

Which isotope of carbon is radioactive?

carbon-14 The rare carbon-14 (14C) isotope contains eight neutrons in its nucleus. Unlike 12C and 13C, this isotope is unstable, or radioactive.

How much of the human body is carbon 12?

Almost 99% of the mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus .Elemental composition list.ElementCarbonFraction of mass0.18Mass (kg)16Atomic percent12Essential in humansYes (organic compounds)56 more columns