Chemical element whole number. For example, the relative atomic mass of chlorine is 35.453 u, which differs greatly from a whole number as it is an average of about 76% chlorine-35 and 24% chlorine-37. Whenever a relative atomic mass value differs by more than 1% from a whole number, it is due to this averaging effect, as significant amounts of more than one isotope are naturally present in a sample of that element. Chemists and nuclear scientists have different definitions of a "pure element". In chemistry, a pure element means a substance whose atoms all (or in practice almost all) have the
Naming of chemical elements element carbon. Even for elements such as nitrogen having only one stable allotrope, a name such as dinitrogen may be used to indicate its molecular structure N as well as its elemental composition. The naming of chemical compounds comprising more than one element is a complex subject, discussed at length in the article on chemical nomenclature. Naming of chemical elements Chemical elements may be named from various sources: sometimes based on the person who discovered it, or the place it was discovered. Some have Latin or Greek roots deriving from something related to the element, for example some use to