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This is a list of chemical elements, sorted by relative atomic mass, or more precisely the standard atomic weights, (most stable isotope for artificial elements) and color coded according to type of element. Each element's atomic number, name, element symbol, and group and period numbers on the periodic table are given. The number in parentheses gives the uncertainty in the "concise notation" defined in the IUPAC reference "whereby standard uncertainty is given in parentheses next to the least significant digits to which it applies", e.g., 1.00794(7) stands for 1.00794 ± 0.00007. For artificial elements the nucleon count of the most stable isotope is listed brackets [] as the atomic mass.
Element categories in the periodic table
| Metals | Metalloids | Nonmetals | Unknown | |||||||
| Alkali metals | Alkaline earth metals | Inner transition elements | Transition elements | Other metals | Other nonmetals | Halogens | Noble gases | |||
| Lanthanides | Actinides | |||||||||
| Atomic Number | Name | Symbol | Relative Atomic Mass | Group | Period |
|---|---|---|---|---|---|
| 1 | Hydrogen | H | 1.00794(7)2 3 4 | 1 | 1 |
| 2 | Helium | He | 4.002602(2)2 4 | 18 | 1 |
| 3 | Lithium | Li | 6.941(2)2 3 4 5 | 1 | 2 |
| 4 | Beryllium | Be | 9.012182(3) | 2 | 2 |
| 5 | Boron | B | 10.811(7)2 3 4 | 13 | 2 |
| 6 | Carbon | C | 12.0107(8)2 4 | 14 | 2 |
| 7 | Nitrogen | N | 14.0067(2)2 4 | 15 | 2 |
| 8 | Oxygen | O | 15.9994(3)2 4 | 16 | 2 |
| 9 | Fluorine | F | 18.9984032(5) | 17 | 2 |
| 10 | Neon | Ne | 20.1797(6)2 3 | 18 | 2 |
| 11 | Sodium (Natrium) | Na | 22.98976928(2) | 1 | 3 |
| 12 | Magnesium | Mg | 24.3050(6) | 2 | 3 |
| 13 | Aluminium (Aluminum) | Al | 26.9815386(8) | 13 | 3 |
| 14 | Silicon | Si | 28.0855(3)4 | 14 | 3 |
| 15 | Phosphorus | P | 30.973762(2) | 15 | 3 |
| 16 | Sulfur | S | 32.065(5)2 4 | 16 | 3 |
| 17 | Chlorine | Cl | 35.453(2)2 3 4 | 17 | 3 |
| 18 | Argon | Ar | 39.948(1)2 4 | 18 | 3 |
| 19 | Potassium (Kalium) | K | 39.0983(1) | 1 | 4 |
| 20 | Calcium | Ca | 40.078(4)2 | 2 | 4 |
| 21 | Scandium | Sc | 44.955912(6) | 3 | 4 |
| 22 | Titanium | Ti | 47.867(1) | 4 | 4 |
| 23 | Vanadium | V | 50.9415(1) | 5 | 4 |
| 24 | Chromium | Cr | 51.9961(6) | 6 | 4 |
| 25 | Manganese | Mn | 54.938045(5) | 7 | 4 |
| 26 | Iron (Ferrum) | Fe | 55.845(2) | 8 | 4 |
| 28 | Nickel | Ni | 58.6934(4) | 10 | 4 |
| 27 | Cobalt | Co | 58.933195(5) | 9 | 4 |
| 29 | Copper (Cuprum) | Cu | 63.546(3)4 | 11 | 4 |
| 30 | Zinc | Zn | 65.38(2) | 12 | 4 |
| 31 | Gallium | Ga | 69.723(1) | 13 | 4 |
| 32 | Germanium | Ge | 72.64(1) | 14 | 4 |
| 33 | Arsenic | As | 74.92160(2) | 15 | 4 |
| 34 | Selenium | Se | 78.96(3)4 | 16 | 4 |
| 35 | Bromine | Br | 79.904(1) | 17 | 4 |
| 36 | Krypton | Kr | 83.798(2)2 3 | 18 | 4 |
| 37 | Rubidium | Rb | 85.4678(3)2 | 1 | 5 |
| 38 | Strontium | Sr | 87.62(1)2 4 | 2 | 5 |
| 39 | Yttrium | Y | 88.90585(2) | 3 | 5 |
| 40 | Zirconium | Zr | 91.224(2)2 | 4 | 5 |
| 41 | Niobium | Nb | 92.906 38(2) | 5 | 5 |
| 42 | Molybdenum | Mo | 95.96(2)2 | 6 | 5 |
| 43 | Technetium | Tc | [98]1 | 7 | 5 |
| 44 | Ruthenium | Ru | 101.07(2)2 | 8 | 5 |
| 45 | Rhodium | Rh | 102.905 50(2) | 9 | 5 |
| 46 | Palladium | Pd | 106.42(1)2 | 10 | 5 |
| 47 | Silver (Argentum) | Ag | 107.8682(2)2 | 11 | 5 |
| 48 | Cadmium | Cd | 112.411(8)2 | 12 | 5 |
| 49 | Indium | In | 114.818(3) | 13 | 5 |
| 50 | Tin (Stannum) | Sn | 118.710(7)2 | 14 | 5 |
| 51 | Antimony (Stibium) | Sb | 121.760(1)2 | 15 | 5 |
| 52 | Tellurium | Te | 127.60(3)2 | 16 | 5 |
| 53 | Iodine | I | 126.904 47(3) | 17 | 5 |
| 54 | Xenon | Xe | 131.293(6)2 3 | 18 | 5 |
| 55 | Caesium (Cesium) | Cs | 132.9054519(2) | 1 | 6 |
| 56 | Barium | Ba | 137.327(7) | 2 | 6 |
| 57 | Lanthanum | La | 138.90547(7)2 | n/a | 6 |
| 58 | Cerium | Ce | 140.116(1)2 | n/a | 6 |
| 59 | Praseodymium | Pr | 140.90765(2) | n/a | 6 |
| 60 | Neodymium | Nd | 144.242(3)2 | n/a | 6 |
| 61 | Promethium | Pm | [145]1 | n/a | 6 |
| 62 | Samarium | Sm | 150.36(2)2 | n/a | 6 |
| 63 | Europium | Eu | 151.964(1)2 | n/a | 6 |
| 64 | Gadolinium | Gd | 157.25(3)2 | n/a | 6 |
| 65 | Terbium | Tb | 158.92535(2) | n/a | 6 |
| 66 | Dysprosium | Dy | 162.500(1)2 | n/a | 6 |
| 67 | Holmium | Ho | 164.930 32(2) | n/a | 6 |
| 68 | Erbium | Er | 167.259(3)2 | n/a | 6 |
| 69 | Thulium | Tm | 168.93421(2) | n/a | 6 |
| 70 | Ytterbium | Yb | 173.054(5)2 | n/a | 6 |
| 71 | Lutetium | Lu | 174.9668(1)2 | 3 | 6 |
| 72 | Hafnium | Hf | 178.49(2) | 4 | 6 |
| 73 | Tantalum | Ta | 180.94788(2) | 5 | 6 |
| 74 | Tungsten (Wolfram) | W | 183.84(1) | 6 | 6 |
| 75 | Rhenium | Re | 186.207(1) | 7 | 6 |
| 76 | Osmium | Os | 190.23(3)2 | 8 | 6 |
| 77 | Iridium | Ir | 192.217(3) | 9 | 6 |
| 78 | Platinum | Pt | 195.084(9) | 10 | 6 |
| 79 | Gold (Aurum) | Au | 196.966569(4) | 11 | 6 |
| 80 | Mercury (Hydrargyrum) | Hg | 200.59(2) | 12 | 6 |
| 81 | Thallium | Tl | 204.3833(2) | 13 | 6 |
| 82 | Lead (Plumbum) | Pb | 207.2(1)2 4 | 14 | 6 |
| 83 | Bismuth | Bi | 208.98040(1) | 15 | 6 |
| 84 | Polonium | Po | [210]1 | 16 | 6 |
| 85 | Astatine | At | [210]1 | 17 | 6 |
| 86 | Radon | Rn | [220]1 | 18 | 6 |
| 87 | Francium | Fr | [223]1 | 1 | 7 |
| 88 | Radium | Ra | [226]1 | 2 | 7 |
| 89 | Actinium | Ac | [227]1 | n/a | 7 |
| 90 | Thorium | Th | 232.03806(2)1 2 | n/a | 7 |
| 91 | Protactinium | Pa | 231.03588(2)1 | n/a | 7 |
| 92 | Uranium | U | 238.02891(3)1 2 3 | n/a | 7 |
| 93 | Neptunium | Np | [237]1 | n/a | 7 |
| 94 | Plutonium | Pu | [244]1 | n/a | 7 |
| 95 | Americium | Am | [243]1 | n/a | 7 |
| 96 | Curium | Cm | [247]1 | n/a | 7 |
| 97 | Berkelium | Bk | [247]1 | n/a | 7 |
| 98 | Californium | Cf | [251]1 | n/a | 7 |
| 99 | Einsteinium | Es | [252]1 | n/a | 7 |
| 100 | Fermium | Fm | [257]1 | n/a | 7 |
| 101 | Mendelevium | Md | [258]1 | n/a | 7 |
| 102 | Nobelium | No | [259]1 | n/a | 7 |
| 103 | Lawrencium | Lr | [262]1 | 3 | 7 |
| 104 | Rutherfordium | Rf | [261]1 | 4 | 7 |
| 105 | Dubnium | Db | [262]1 | 5 | 7 |
| 106 | Seaborgium | Sg | [266]1 | 6 | 7 |
| 107 | Bohrium | Bh | [264]1 | 7 | 7 |
| 108 | Hassium | Hs | [277]1 | 8 | 7 |
| 109 | Meitnerium | Mt | [268]1 | 9 | 7 |
| 110 | Darmstadtium | Ds | [271]1 | 10 | 7 |
| 111 | Roentgenium | Rg | [272]1 | 11 | 7 |
| 112 | Ununbium | Uub | [285]1 | 12 | 7 |
| 113 | Ununtrium | Uut | [284]1 | 13 | 7 |
| 114 | Ununquadium | Uuq | [289]1 | 14 | 7 |
| 115 | Ununpentium | Uup | [288]1 | 15 | 7 |
| 116 | Ununhexium | Uuh | [292]1 | 16 | 7 |
| 118 | Ununoctium | Uuo | [294]1 | 18 | 7 |
Element categories in the periodic table
| Metals | Metalloids | Nonmetals | Unknown | |||||||
| Alkali metals | Alkaline earth metals | Inner transition elements | Transition elements | Other metals | Other nonmetals | Halogens | Noble gases | |||
| Lanthanides | Actinides | |||||||||
Notes
- Note 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, three elements, Thorium, Protactinium, and Uranium, have a characteristic terrestrial isotopic composition, and thus their standard atomic weights are given.
- Note 2: The isotopic composition of this element varies in some geological specimens, and the variation may exceed the uncertainty stated in the table.
- Note 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.
- Note 4: The isotopic composition varies in terrestrial material such that a more precise atomic weight can not be given.
- Note 5: The atomic weight of commercial Lithium can vary between 6.939 and 6.996—analysis of the specific material is necessary to find a more accurate value.
References
- Atomic Weights of the Elements 2005, Pure Appl. Chem. 78(11), 2051-2066, 2006. Retrieved May 7, 2008. Atomic weights of elements with atomic numbers 1-27, 29, 31-41, 43-69, 72-109 taken from this source.
- IUPAC Standard Atomic Weights Revised (2007). Atomic weights of elements with atomic numbers of 28, 30, 42, 70 & 71 taken from this source.
- WebElements Periodic Table. Retrieved June 30, 2005. Atomic weights of elements with atomic numbers of 110-116 taken from this source.
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