Vitamin B12, also known as cyanocobalamin, is a water-soluble vitamin that is part of the B vitamin family. B vitamins help support adrenal function, help calm and maintain a healthy nervous system, and are necessary for key metabolic processes.
For each of the 80 stable elements, the number of the stable isotopes is given. Only 90 isotopes are expected to be perfectly stable, and an additional 163 are energetically unstable, but have never been observed to decay. Thus, 253 isotopes (nuclides) are stable by definition (including tantalum-180m, for which no decay has yet been observed).
It is nonmetallic and tetravalentâmaking four electrons available to form covalent chemical bonds. Three isotopes occur naturally, 12C and 13C being stable, while 14C is a radioactive isotope, decaying with a half-life of about 5,730 years. Carbon is one of the few elements known since antiquity.