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).
If an atom of tin has a mass number of 118 and an atomic number of 50, how many neutrons are in its nucleus? 68 Most calcium atoms have an atomic number of 20 and a mass number of 49, but some calcium atoms have a mass number of 48. What word could you use to describe these two kinds of calcium atoms? Isotopes