The following is a list of the 118 identified chemical elements.
List
Notes
- ^1 The element does not have any stable nuclides, and a value in brackets, e.g. [209], indicates the mass number of the longest-lived isotope of the element. However, four such elements, bismuth, thorium, protactinium, and uranium, have characteristic terrestrial isotopic compositions, and thus their standard atomic weights are given.
- ^2 The isotopic composition of this element varies in some geological specimens, and the variation may exceed the uncertainty stated in the table.
- ^3 The isotopic composition of the element can vary in commercial materials, which can cause the atomic weight to deviate significantly from the given value.
- ^4 The isotopic composition varies in terrestrial material such that a more precise atomic weight can not be given.
- ^5 The atomic weight of commercial lithium can vary between 6.939 and 6.996â€"analysis of the specific material is necessary to find a more accurate value.
- ^6 This element does not solidify at a pressure of one atmosphere. The value listed above, 0.95 K, is the temperature at which helium does solidify at a pressure of 25 atmospheres.
- ^7 This element sublimes at one atmosphere of pressure
- ^8 The transuranic elements 99 and above do not occur naturally, but some of them can be produced artificially.
- ^9 The value listed is the conventional atomic-weight value suitable for trade and commerce. The actual value may differ depending on the isotopic composition of the sample. Since 2009, IUPAC provides the standard atomic-weight values for these elements using the interval notation. The corresponding standard atomic weights are:
- Hydrogen: [1.00784, 1.00811]
- Lithium: [6.938, 6.997]
- Boron: [10.806, 10.821]
- Carbon: [12.0096, 12.0116]
- Nitrogen: [14.00643, 14.00728]
- Oxygen: [15.99903, 15.99977]
- Magnesium: [24.304, 24.307]
- Silicon: [28.084, 28.086]
- Sulfur: [32.059, 32.076]
- Chlorine: [35.446, 35.457]
- Bromine: [79.901, 79.907]
- Thallium: [204.382, 204.385]
- ^10 Electronegativity on the Pauling scale. Standard symbol: χ
- ^11 The value has not been precisely measured, usually because of the element's short half-life; the value given in parentheses is a prediction.
- ^12 With error bars: 357+112
âˆ'108 K. - ^13 This predicted value is for liquid ununoctium, not gaseous ununoctium.
References
- M. E. Wieser et al. (2013). "Atomic weights of the elements 2011 (IUPAC Technical Report)". Pure Appl. Chem. (IUPAC) 85 (5): 1047â€"1078. doi:10.1351/PAC-REP-13-03-02. CS1 maint: Explicit use of et al. (link) (for standard atomic weights of elements)
- Sonzogni , Alejandro. "Interactive Chart of Nuclides". National Nuclear Data Center: Brookhaven National Laboratory. Retrieved 2008-06-06. (for atomic weights of elements with atomic numbers 103â€"118)
External links
- Atoms made thinkable, an interactive visualisation of the elements allowing physical and chemical properties to be compared