Chemical element notation

Dr Daniel J Bell et al.

The notation of the 118 known chemical elements is prescribed by the IUPAC (International Union for Pure and Applied Chemistry) 1

Each chemical element has a long name and a symbol. In English the long name is only capitalized as part of title or sentence case. Chemical element names are not proper nouns and therefore are otherwise always in lower case.

Symbols are either one or two letters (e.g. F, Xe, U etc.):

  • the initial letter is always capitalized
  • if there is a second letter it is always in lower case

Correct usages:

  • Carbon's atomic number is 6 which means it has 6 protons in each of its atoms.
  • The fluorine atom used in PET imaging is a radioisotope with a mass number of 18.

See also

Help and Style Guide
Share article

Article information

rID: 68259
Section: Pathology
Synonyms or Alternate Spellings:
  • Elements (notation)

Support Radiopaedia and see fewer ads

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.