Chemical symbol
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In chemistry, a symbol is a code for a chemical element. It is usually derived from the modern name of the element but for some elements it is derived from the name in Latin.[nb 1] For example, "He" is the symbol for helium (English name, not known in ancient Roman times), "Pb" for lead (plumbum in Latin), "Hg" for mercury (hydrargyrum in Greek), "W" for tungsten (wolfram in German, not known in Roman times). Only the first letter is capitalized.
Temporary symbols assigned to newly or not-yet synthesized elements use 3-letter symbols based on their atomic numbers. For example, "Uno" was the temporary symbol for hassium which had the temporary name of unniloctium and "Uuo" is the symbol for ununoctium (temporary name) with the atomic mass 118.
Chemical symbols may be modified by the use of prepended superscripts or subscripts to specify a particular isotope of an atom. Additionally, appended superscripts may be used to indicate the ionization or oxidation state of an element. They are widely used in chemistry and they have been officially chosen by the International Union of Pure and Applied Chemistry. There are also some historical symbols that are no longer officially used.
Attached subscripts or superscripts specifying a nucleotide or molecule have the following meanings and positions:
- The nucleon number (mass number) is shown in the left superscript position (e.g., 14N)
- The proton number (atomic number) may be indicated in the left subscript position (e.g., 64Gd)
- If necessary, a state of ionization or an excited state may be indicated in the right superscript position (e.g., state of ionization Ca2+). In astronomy, non-ionised atomic hydrogen is often known as "H I", and ionised hydrogen as "H II".[1]
- The number of atoms of an element in a molecule or chemical compound is shown in the right subscript position (e.g., N2 or Fe2O3)
- A radical is indicated by a dot on the right side (e.g., Cl· for a chloride radical)
In Chinese, each chemical element has a dedicated character, usually created for the purpose (see Chemical elements in East Asian languages). However, Latin symbols are also used, especially in formulas.
A list of current, dated, as well as proposed and historical signs and symbols is included here with its signification. Also given is each element's atomic number, atomic weight or the atomic mass of the most stable isotope, group and period numbers on the periodic table, and etymology of the symbol.
Symbols
Symbol | Name | Etymology of symbol | Atomic number | Relative atomic mass | Group | Period | Metallic character |
---|---|---|---|---|---|---|---|
Ac | Actinium | Greek aktinos (ray) | 89 | [nb 2] | [227]7 | style="background-color:#ff99cc" | Actinide | |
Ag | Silver | Latin argentum (silver) | 47 | [nb 3] | 107.8682(2)11 | 5 | style="background-color:#ffc0c0" | Transition metal |
Al | Aluminium (aluminum) | Latin alumen (alum) | 13 | 26.9815386(8) | 13 | 3 | style="background-color:#cccccc" | Post-transition metal |
Am | Americium | the Americas | 95 | [nb 2] | [243]7 | style="background-color:#ff99cc" | Actinide | |
Ar | Argon | Greek argon (inert) | 18 | [nb 3][nb 4] | 39.948(1)18 | 3 | Noble gas |
As | Arsenic | Greek arsenikos (male) | 33 | 74.92160(2) | 15 | 4 | Metalloid |
At | Astatine | Greek astatos (unstable) | 85 | [nb 2] | [210]17 | 6 | Metalloid |
Au | Gold | Latin aurum (gold) | 79 | 196.966569(4) | 11 | 6 | style="background-color:#ffc0c0" | Transition metal |
B | Boron | borax | 5 | [nb 3][nb 4][nb 5] | 10.811(7)13 | 2 | Metalloid |
Ba | Barium | Greek barys (density) | 56 | 137.327(7) | 2 | 6 | style="background-color:#ffdead" | Alkaline earth metal |
Be | Beryllium | beryl | 4 | 9.012182(3) | 2 | 2 | style="background-color:#ffdead" | Alkaline earth metal |
Bh | Bohrium | Niels Bohr | 107 | [nb 2] | [264]7 | 7 | style="background-color:#ffc0c0" | Transition metal |
Bi | Bismuth | German wiss muth (white-mass), becoming bismuth in English | 83 | 208.98040(1) | 15 | 6 | style="background-color:#cccccc" | Post-transition metal |
Bk | Berkelium | Berkeley, California | 97 | [nb 2] | [247]7 | style="background-color:#ff99cc" | Actinide | |
Br | Bromine | Greek bromos (stench) | 35 | 79.904(1) | 17 | 4 | style="background-color:#e7ff8f" | Diatomic nonmetal |
C | Carbon | Latin carbo (charcoal) | 6 | [nb 3][nb 4] | 12.0107(8)14 | 2 | style="background-color:#a1ffc3" | Polyatomic nonmetal |
Ca | Calcium | Latin calx (lime) | 20 | [nb 3] | 40.078(4)2 | 4 | style="background-color:#ffdead" | Alkaline earth metal |
Cd | Cadmium | Greek kadmia (earth) | 48 | [nb 3] | 112.411(8)12 | 5 | style="background-color:#ffc0c0" | Transition metal |
Ce | Cerium | Ceres | 58 | [nb 3] | 140.116(1)6 | style="background-color:#ffbfff" | Lanthanide | |
Cf | Californium | State and University of California | 98 | [nb 2] | [251]7 | style="background-color:#ff99cc" | Actinide | |
Cl | Chlorine | Greek chloros (green-yellow) | 17 | [nb 3][nb 4][nb 5] | 35.453(2)17 | 3 | style="background-color:#e7ff8f" | Diatomic nonmetal |
Cm | Curium | Pierre and Marie Curie and the traditional -um ending | 96 | [nb 2] | [247]7 | style="background-color:#ff99cc" | Actinide | |
Cn | Copernicium | Nicolaus Copernicus | 112 | [nb 2] | [285]12 | 7 | style="background-color:#ffc0c0" | Transition metal |
Co | Cobalt | German kobold | 27 | 58.933195(5) | 9 | 4 | style="background-color:#ffc0c0" | Transition metal |
Cr | Chromium | Greek chroma (color) | 24 | 51.9961(6) | 6 | 4 | style="background-color:#ffc0c0" | Transition metal |
Cs | Caesium (cesium) | Latin caesius (sky blue) | 55 | 132.9054519(2) | 1 | 6 | style="background-color:#ff9d9d" | Alkali metal |
Cu | Copper | Latin Cuprum (Cyprus) | 29 | [nb 4] | 63.546(3)11 | 4 | style="background-color:#ffc0c0" | Transition metal |
Db | Dubnium | Dubna, Russia | 105 | [nb 2] | [262]5 | 7 | style="background-color:#ffc0c0" | Transition metal |
Ds | Darmstadtium | Darmstadt, Germany | 110 | [nb 2] | [271]10 | 7 | Unknown |
Dy | Dysprosium | Greek dysprositos | 66 | [nb 3] | 162.500(1)6 | style="background-color:#ffbfff" | Lanthanide | |
Er | Erbium | Ytterby, Sweden | 68 | [nb 3] | 167.259(3)6 | style="background-color:#ffbfff" | Lanthanide | |
Es | Einsteinium | Albert Einstein | 99 | [nb 2] | [252]7 | style="background-color:#ff99cc" | Actinide | |
Eu | Europium | Europe | 63 | [nb 3] | 151.964(1)6 | style="background-color:#ffbfff" | Lanthanide | |
F | Fluorine | Latin fluo (flow) | 9 | 18.9984032(5) | 17 | 2 | style="background-color:#e7ff8f" | Diatomic nonmetal |
Fe | Iron | Latin ferrum (iron) | 26 | 55.845(2) | 8 | 4 | style="background-color:#ffc0c0" | Transition metal |
Fl | Flerovium | Flerov Laboratory of Nuclear Reactions | 114 | [nb 2] | [289]14 | 7 | Unknown |
Fm | Fermium | Enrico Fermi | 100 | [nb 2] | [257]7 | style="background-color:#ff99cc" | Actinide | |
Fr | Francium | France | 87 | [nb 2] | [223]1 | 7 | style="background-color:#ff9d9d" | Alkali metal |
Ga | Gallium | Latin Gallia (Gaul) | 31 | 69.723(1) | 13 | 4 | style="background-color:#cccccc" | Post-transition metal |
Gd | Gadolinium | gadolinite | 64 | [nb 3] | 157.25(3)6 | style="background-color:#ffbfff" | Lanthanide | |
Ge | Germanium | Germany | 32 | 72.64(1) | 14 | 4 | Metalloid |
H | Hydrogen | Greek hydor gennao (liquid-produce) | 1 | [nb 3][nb 4][nb 5] | 1.00794(7)1 | 1 | style="background-color:#e7ff8f" | Diatomic nonmetal |
He | Helium | Greek helios (Sun) | 2 | [nb 3][nb 4] | 4.002602(2)18 | 1 | Noble gas |
Hf | Hafnium | Latin Hafnia (Copenhagen) | 72 | 178.49(2) | 4 | 6 | style="background-color:#ffc0c0" | Transition metal |
Hg | Mercury | Greek hydrargyrum (liquid silver) | 80 | 200.59(2) | 12 | 6 | style="background-color:#ffc0c0" | Transition metal |
Ho | Holmium | Latin Holmia (Stockholm) | 67 | 164.930 32(2) | 6 | style="background-color:#ffbfff" | Lanthanide | |
Hs | Hassium | Hesse, Germany | 108 | [nb 2] | [277]8 | 7 | style="background-color:#ffc0c0" | Transition metal |
I | Iodine | Greek ioeides (violet) | 53 | 126.904 47(3) | 17 | 5 | style="background-color:#e7ff8f" | Diatomic nonmetal |
In | Indium | indigo blue | 49 | 114.818(3) | 13 | 5 | style="background-color:#cccccc" | Post-transition metal |
Ir | Iridium | Greek iris (rainbow) | 77 | 192.217(3) | 9 | 6 | style="background-color:#ffc0c0" | Transition metal |
K | Potassium | Latin kalium (potassium) | 19 | 39.0983(1) | 1 | 4 | style="background-color:#ff9d9d" | Alkali metal |
Kr | Krypton | Greek kryptos (concealment) | 36 | [nb 3][nb 5] | 83.798(2)18 | 4 | Noble gas |
La | Lanthanum | Greek lanthano (escape) | 57 | [nb 3] | 138.90547(7)6 | style="background-color:#ffbfff" | Lanthanide | |
Li | Lithium | Greek lithos (rock) | 3 | [nb 3][nb 4][nb 5][nb 6] | 6.941(2)1 | 2 | style="background-color:#ff9d9d" | Alkali metal |
Lr | Lawrencium | Ernest O. Lawrence | 103 | [nb 2] | [262]3 | 7 | style="background-color:#ff99cc" | Actinide |
Lu | Lutetium | Latin Lutetia (Paris) | 71 | [nb 3] | 174.967(1)3 | 6 | style="background-color:#ffbfff" | Lanthanide |
Lv | Livermorium | Lawrence Livermore National Laboratory | 116 | [nb 2] | [292]16 | 7 | Unknown |
Md | Mendelevium | Dmitri Mendeleyev | 101 | [nb 2] | [258]7 | style="background-color:#ff99cc" | Actinide | |
Mg | Magnesium | Magnesia, Greece | 12 | 24.3050(6) | 2 | 3 | style="background-color:#ffdead" | Alkaline earth metal |
Mn | Manganese | Greek magnes (magnet) | 25 | 54.938045(5) | 7 | 4 | style="background-color:#ffc0c0" | Transition metal |
Mo | Molybdenum | Greek molybdos (lead) | 42 | [nb 3] | 95.94(2)6 | 5 | style="background-color:#ffc0c0" | Transition metal |
Mt | Meitnerium | Lise Meitner | 109 | [nb 2] | [268]9 | 7 | Unknown |
N | Nitrogen | Greek nitron (niter) | 7 | [nb 3][nb 4] | 14.0067(2)15 | 2 | style="background-color:#e7ff8f" | Diatomic nonmetal |
Na | Sodium | Latin natrium (sodium) | 11 | 22.98976928(2) | 1 | 3 | style="background-color:#ff9d9d" | Alkali metal |
Nb | Niobium | Niobe | 41 | 92.906 38(2) | 5 | 5 | style="background-color:#ffc0c0" | Transition metal |
Nd | Neodymium | Greek neos didymos (novelty-twin) | 60 | [nb 3] | 144.242(3)6 | style="background-color:#ffbfff" | Lanthanide | |
Ne | Neon | Greek neos (novelty) | 10 | [nb 3][nb 5] | 20.1797(6)18 | 2 | Noble gas |
Ni | Nickel | German kupfernickel (nickeline) | 28 | 58.6934(2) | 10 | 4 | style="background-color:#ffc0c0" | Transition metal |
No | Nobelium | Alfred Nobel | 102 | [nb 2] | [259]7 | style="background-color:#ff99cc" | Actinide | |
Np | Neptunium | Neptune | 93 | [nb 2] | [237]7 | style="background-color:#ff99cc" | Actinide | |
O | Oxygen | Greek oxys (acid) | 8 | [nb 3][nb 4] | 15.9994(3)16 | 2 | style="background-color:#e7ff8f" | Diatomic nonmetal |
Os | Osmium | Greek osme (odor) | 76 | [nb 3] | 190.23(3)8 | 6 | style="background-color:#ffc0c0" | Transition metal |
P | Phosphorus | Greek phosphoros (light bearer) | 15 | 30.973762(2) | 15 | 3 | style="background-color:#a1ffc3" | Polyatomic nonmetal |
Pa | Protactinium | Greek protos and actinium | 91 | [nb 2] | 231.03588(2)7 | style="background-color:#ff99cc" | Actinide | |
Pb | Lead | Latin plumbum (lead) | 82 | [nb 3][nb 4] | 207.2(1)14 | 6 | style="background-color:#cccccc" | Post-transition metal |
Pd | Palladium | Pallas (genitive Pallados) | 46 | [nb 3] | 106.42(1)10 | 5 | style="background-color:#ffc0c0" | Transition metal |
Pm | Promethium | Prometheus | 61 | [nb 2] | [145]6 | style="background-color:#ffbfff" | Lanthanide | |
Po | Polonium | Poland | 84 | [nb 2] | [210]16 | 6 | style="background-color:#cccccc" | Post-transition metal |
Pr | Praseodymium | Greek prasios (green) | 59 | 140.90765(2) | 6 | style="background-color:#ffbfff" | Lanthanide | |
Pt | Platinum | Spanish platina (silver) | 78 | 195.084(9) | 10 | 6 | style="background-color:#ffc0c0" | Transition metal |
Pu | Plutonium | Pluto | 94 | [nb 2] | [244]7 | style="background-color:#ff99cc" | Actinide | |
Ra | Radium | Latin radius (ray) | 88 | [nb 2] | [226]2 | 7 | style="background-color:#ffdead" | Alkaline earth metal |
Rb | Rubidium | Latin rubidus (red) | 37 | [nb 3] | 85.4678(3)1 | 5 | style="background-color:#ff9d9d" | Alkali metal |
Re | Rhenium | German Rheinprovinz | 75 | 186.207(1) | 7 | 6 | style="background-color:#ffc0c0" | Transition metal |
Rf | Rutherfordium | Ernest Rutherford | 104 | [nb 2] | 2614 | 7 | style="background-color:#ffc0c0" | Transition metal |
Rg | Roentgenium | Wilhelm Conrad Röntgen | 111 | [nb 2] | [272]11 | 7 | Unknown |
Rh | Rhodium | Greek rhodon (rose) | 45 | 102.905 50(2) | 9 | 5 | style="background-color:#ffc0c0" | Transition metal |
Rn | Radon | radium and emanation | 86 | [nb 2] | [220]18 | 6 | Noble gas |
Ru | Ruthenium | Latin Ruthenia (Russia) | 44 | [nb 3] | 101.07(2)8 | 5 | style="background-color:#ffc0c0" | Transition metal |
S | Sulfur (Sulphur) | Latin sulfur | 16 | [nb 3][nb 4] | 32.065(5)16 | 3 | style="background-color:#a1ffc3" | Polyatomic nonmetal |
Sb | Antimony | Latin stibium (eye liner) | 51 | [nb 3] | 121.760(1)15 | 5 | Metalloid |
Sc | Scandium | Scandinavia | 21 | 44.955912(6) | 3 | 4 | style="background-color:#ffc0c0" | Transition metal |
Se | Selenium | Greek selene (Moon) | 34 | [nb 4] | 78.96(3)16 | 4 | style="background-color:#a1ffc3" | Polyatomic nonmetal |
Sg | Seaborgium | Glenn T. Seaborg | 106 | [nb 2] | [266]6 | 7 | style="background-color:#ffc0c0" | Transition metal |
Si | Silicon | Latin silex (flint) | 14 | [nb 4] | 28.0855(3)14 | 3 | Metalloid |
Sm | Samarium | samarskite | 62 | [nb 3] | 150.36(2)6 | style="background-color:#ffbfff" | Lanthanide | |
Sn | Tin | Latin stannum (tin) | 50 | [nb 3] | 118.710(7)14 | 5 | style="background-color:#cccccc" | Post-transition metal |
Sr | Strontium | Strontian | 38 | [nb 3][nb 4] | 87.62(1)2 | 5 | style="background-color:#ffdead" | Alkaline earth metal |
Ta | Tantalum | King Tantalus | 73 | 180.94788(2) | 5 | 6 | style="background-color:#ffc0c0" | Transition metal |
Tb | Terbium | Ytterby, Sweden | 65 | 158.92535(2) | 6 | style="background-color:#ffbfff" | Lanthanide | |
Tc | Technetium | Greek technetos (artificial) | 43 | [nb 2] | [98]7 | 5 | style="background-color:#ffc0c0" | Transition metal |
Te | Tellurium | Greek tellus (Earth) | 52 | [nb 3] | 127.60(3)16 | 5 | Metalloid |
Th | Thorium | Thor | 90 | [nb 2][nb 3] | 232.03806(2)7 | style="background-color:#ff99cc" | Actinide | |
Ti | Titanium | the Titans | 22 | 47.867(1) | 4 | 4 | style="background-color:#ffc0c0" | Transition metal |
Tl | Thallium | Greek thallos (shoot) | 81 | 204.3833(2) | 13 | 6 | style="background-color:#cccccc" | Post-transition metal |
Tm | Thulium | Thule and the traditional -ium ending | 69 | 168.93421(2) | 6 | style="background-color:#ffbfff" | Lanthanide | |
U | Uranium | Uranus | 92 | [nb 2][nb 3][nb 5] | 238.02891(3)7 | style="background-color:#ff99cc" | Actinide | |
Uuo | Ununoctium | Latin uni, uni, and oct (one, one, eight) | 118 | [nb 2] | [294]18 | 7 | Unknown |
Uup | Ununpentium | Latin uni, uni, and Greek pent (one, one, five) | 115 | [nb 2] | [288]15 | 7 | Unknown |
Uus | Ununseptium | Latin uni, uni, and sept (one, one, seven) | 117 | [nb 2] | [294]17 | 7 | Unknown |
Uut | Ununtrium | Latin uni, uni, and Greek tri (one, one, three) | 113 | [nb 2] | [284]13 | 7 | Unknown |
V | Vanadium | Vanadis | 23 | 50.9415(1) | 5 | 4 | style="background-color:#ffc0c0" | Transition metal |
W | Tungsten | German wolfram (wolf-froth) | 74 | 183.84(1) | 6 | 6 | style="background-color:#ffc0c0" | Transition metal |
Xe | Xenon | Greek xenos (alien) | 54 | [nb 3][nb 5] | 131.293(6)18 | 5 | Noble gas |
Y | Yttrium | Ytterby, Sweden | 39 | 88.90585(2) | 3 | 5 | style="background-color:#ffc0c0" | Transition metal |
Yb | Ytterbium | Ytterby, Sweden | 70 | [nb 3] | 173.04(3)6 | style="background-color:#ffbfff" | Lanthanide | |
Zn | Zinc | German zin (tin) | 30 | 65.409(4) | 12 | 4 | style="background-color:#ffc0c0" | Transition metal |
Zr | Zirconium | zircon | 40 | [nb 3] | 91.224(2)4 | 5 | style="background-color:#ffc0c0" | Transition metal |
Antimatter atoms are denoted by a bar above the symbol for their matter counterpart, so e.g. H is the symbol for antihydrogen.
Symbols not currently used
The following is a list of symbols formerly used or suggested for elements, including symbols for placeholder names and names given by discredited claimants for discovery.
Chemical symbol | Name | Atomic number | Origin of symbol | Why not used |
---|---|---|---|---|
A | Argon | 18 | Current symbol is Ar. | [nb 7] |
Ab | Alabamine | 85 | Discredited claim to discovery of astatine. | [nb 8] |
Ad | Aldebaranium | 70 | Former name of ytterbium. | [nb 8] |
Am | Alabamium | 85 | Discredited claim to discovery of astatine. The symbol is now used for americium | [nb 8] |
An | Athenium | 99 | Proposed name for einsteinium. | [nb 9] |
Ao | Ausonium | 93 | Discredited claim to discovery of neptunium. | [nb 8] |
Az | Azote | 7 | Former name for nitrogen. | [nb 7] |
Bo | Boron | 5 | Current symbol is B. | [nb 7] |
Bv | Brevium | 91 | Former name for protactinium. | [nb 7] |
Bz | Berzelium | 59 | Suggested name for praseodymium. | [nb 9] |
Cb | Columbium | 41 | Former name of niobium. | [nb 7] |
Cb | Columbium | 95 | Suggested name for americium. | [nb 9] |
Ch | Chromium | 24 | Current symbol is Cr. | [nb 7] |
Cl | Columbium | 41 | Former name of niobium. The symbol is now used for chlorine. | [nb 7] |
Cp | Cassiopeium | 71 | Former name for lutetium. | [nb 7] |
Cp | Copernicium | 112 | Current symbol is Cn. | [nb 7] |
Ct | Centurium | 100 | Proposed name for fermium. | [nb 9] |
Ct | Celtium | 72 | Former name of hafnium. | [nb 7] |
Da | Danubium | 43 | Suggested name for technetium. | [nb 9] |
Db | Dubnium | 104 | Proposed name for rutherfordium. The symbol and name were used for element 105. | [nb 7][nb 9] |
Di | Didymium | Mixture of the elements praseodymium and neodymium. Mosander wrongly believed didymium to be an element | [2] | |
E | Einsteinium | 99 | Current symbol is Es. | [nb 7] |
Ea | Ekaaluminium | 31 | Name given by Mendeleev to an as of then undiscovered element. When discovered, gallium closely matched the prediction. | [nb 9][nb 10] |
Eb | Ekaboron | 21 | Name given by Mendeleev to an as of then undiscovered element. When discovered, scandium closely matched the prediction. | [nb 9][nb 10] |
El | Ekaaluminium | 31 | Name given by Mendeleev to an as of then undiscovered element. When discovered, gallium closely matched the prediction. | [nb 9][nb 10] |
Em | Emanation | 86 | Also called "radium emanation", the name was originally given by Friedrich Ernst Dorn in 1900. In 1923, this element officially became radon (the name given at one time to 222Rn, an isotope identified in the decay chain of radium). | [nb 7] |
Em | Ekamanganese | 43 | Name given by Mendeleev to an as of then undiscovered element. When discovered, technetium closely matched the prediction. | [nb 9][nb 10] |
Es | Ekasilicon | 32 | Name given by Mendeleev to an as of then undiscovered element. When discovered, germanium closely matched the prediction. The symbol is now used for einsteinium. | [nb 9][nb 10] |
Es | Esperium | 94 | Discredited claim to discovery of plutonium. The symbol is now used for einsteinium. | [nb 8] |
Fa | Francium | 87 | Current symbol is Fr. | [nb 7] |
Fl | Fluorine | 9 | Current symbol is F. The symbol is now used for flerovium. | [nb 7] |
Fl | Florentium | 61 | Discredited claim to discovery of promethium. The symbol is now used for flerovium. | [nb 8] |
Fr | Florentium | 61 | Discredited claim to discovery of promethium. The symbol is now used for francium. | [nb 8] |
G | Glucinium | 4 | Former name of beryllium. | [nb 7] |
Gl | Glucinium | 4 | Former name of beryllium. | [nb 7] |
Ha | Hahnium | 105 | Proposed name for dubnium. | [nb 9] |
Hn | Hahnium | 108 | Proposed name for hassium. | [nb 9] |
Hy | Mercury | 80 | Current symbol is Hg. | [nb 7] |
I | Iridium | 77 | Current symbol is Ir. The symbol is now used for iodine. | [nb 7] |
Il | Illinium | 61 | Discredited claim to discovery of promethium. | [nb 8] |
J | Jodium | 53 | Former name of iodine. | [nb 7] |
Jg | Jargonium | 72 | Discredited claim to discovery of hafnium. | [nb 8] |
Jl | Joliotium | 105 | Proposed name for dubnium. | [nb 9] |
Ku | Kurchatovium | 104 | Proposed name for rutherfordium. | [nb 9] |
Lw | Lawrencium | 103 | Current symbol is Lr. | [nb 7] |
M | Muriaticum | 17 | Former name of chlorine. | [nb 7] |
Ma | Manganese | 25 | Current symbol is Mn. | [nb 7] |
Ma | Masurium | 43 | Disputed claim to discovery of technetium. | [nb 8] |
Md | Mendelevium | 97 | Proposed name for berkelium. The symbol and name were later used for element 101. | [nb 7][nb 9] |
Me | Mendelevium | 68 | Suggested name for erbium. | [nb 7] |
Ml | Moldavium | 87 | Suggested name for francium. | [nb 9] |
Ms | Magnesium | 12 | Current symbol is Mg. | [nb 7] |
Ms | Masrium | 49 | Discredited claim of discovery of indium. | [nb 8] |
Mt | Meitnium | 91 | Suggested name for protactinium. The symbol is now used for meitnerium. | [nb 9] |
Mv | Mendelevium | 101 | Current symbol is Md. | [nb 7] |
Ng | Norwegium | 72 | Discredited claim to discovery of hafnium. | [nb 8] |
No | Norium | 72 | Discredited claim to discovery of hafnium. The symbol is now used for nobelium. | [nb 8] |
Ns | Nielsbohrium | 105 | Proposed name for dubnium. | [nb 9] |
Ns | Nielsbohrium | 107 | Proposed name for bohrium. | [nb 9] |
Nt | Niton | 86 | Former name for radon. | [nb 7] |
Ny | Neoytterbium | 70 | Former name of ytterbium. | [nb 7] |
Od | Odinium | 62 | Suggested name for samarium. | [nb 9] |
P | Lead | 82 | Current symbol is Pb. The symbol is now used for phosphorus. | [nb 7] |
Pa | Palladium | 46 | Current symbol is Pd. The symbol is now used for protactinium. | [nb 7] |
Pe | Pelopium | 41 | Former name for niobium. | [nb 7] |
Pl | Palladium | 46 | Current symbol is Pd. | [nb 7] |
Po | Potassium | 19 | Current symbol is K. The letters were later used for polonium. | [nb 7] |
R | Rhodium | 45 | Current symbol is Rh. | [nb 7] |
Rf | Rutherfordium | 106 | Proposed name for seaborgium. The symbol and name were instead used for element 104. | [nb 7][nb 9] |
Ro | Rhodium | 45 | Current symbol is Rh. | [nb 7] |
Sa | Samarium | 62 | Current symbol is Sm. | [nb 7] |
So | Sodium | 11 | Current symbol is Na. | [nb 7] |
Sp | Spectrium | 70 | Suggested name for ytterbium. | [nb 9] |
St | Tin | 50 | Current symbol is Sn. | [nb 7] |
St | Antimony | 51 | Current symbol is Sb. | [nb 7] |
Tn | Tungsten | 74 | Current symbol is W. | [nb 7] |
Tu | Thulium | 69 | Current symbol is Tm. | [nb 7] |
Tu | Tungsten | 74 | Current symbol is W. | [nb 7] |
Ty | Tyrium | 60 | Suggested name for neodymium. | [nb 9] |
Unb | Unnilbium | 102 | Temporary name given to nobelium until it was permanently named by IUPAC. | [nb 10] |
Une | Unnilennium | 109 | Temporary name given to meitnerium until it was permanently named by IUPAC. | [nb 10] |
Unh | Unnilhexium | 106 | Temporary name given to seaborgium until it was permanently named by IUPAC. | [nb 10] |
Uno | Unniloctium | 108 | Temporary name given to hassium until it was permanently named by IUPAC. | [nb 10] |
Unp | Unnilpentium | 105 | Temporary name given to dubnium until it was permanently named by IUPAC. | [nb 10] |
Unq | Unnilquadium | 104 | Temporary name given to rutherfordium until it was permanently named by IUPAC. | [nb 10] |
Uns | Unnilseptium | 107 | Temporary name given to bohrium until it was permanently named by IUPAC. | [nb 10] |
Unt | Unniltrium | 103 | Temporary name given to lawrencium until it was permanently named by IUPAC. | [nb 10] |
Unu | Unnilunium | 101 | Temporary name given to mendelevium until it was permanently named by IUPAC. | [nb 10] |
Uub | Ununbium | 112 | Temporary name given to copernicium until it was permanently named by IUPAC. | [nb 10] |
Uuh | Ununhexium | 116 | Temporary name given to livermorium until it was permanently named by IUPAC. | [nb 10] |
Uun | Ununnilium | 110 | Temporary name given to darmstadtium until it was permanently named by IUPAC. | [nb 10] |
Uuq | Ununquadium | 114 | Temporary name given to flerovium until it was permanently named by IUPAC. | [nb 10] |
Uuu | Unununium | 111 | Temporary name given to roentgenium until it was permanently named by IUPAC. | [nb 10] |
Ur | Uranium | 92 | Current symbol is U. | [nb 7] |
Vi | Virginium | 87 | Discredited claim to discovery of francium. | [nb 8] |
Vm | Virginium | 87 | Discredited claim to discovery of francium. | [nb 8] |
Yt | Yttrium | 39 | Current symbol is Y. | [nb 7] |
Pictographic symbols
The following is a list of pictographic symbols employed to symbolize elements known since ancient times (for example to the alchemists). Not included in this list are symbolic representations of substances previously called elements (such as certain rare earth mineral blends and the classical elements fire and water of ancient philosophy) which are known today to be multi-atomic. Also not included are symbolic representations currently used for elements in other languages such as the Chinese characters for elements. Modern alphabetic notation was introduced in 1814 by Jöns Jakob Berzelius.
Chemical symbol | Original name | Modern name | Atomic number | Origin of symbol |
---|---|---|---|---|
Hydrogen | Hydrogen | 1 | Daltonian symbol circa 1808. | |
Sulfur | Sulfur | 16 | Alchemical symbol. | |
Pallas | Sulfur | 16 | Alchemical symbol. | |
🜍 | Sulfur | Sulfur | 16 | Alchemical symbol. |
♁ | Sulfur | Sulfur | 16 | Daltonian symbol circa 1808. |
⊛ | Magnesium | Magnesium | 12 | Alchemical symbol. |
♂ | Mars | Iron | 26 | Alchemical symbol. |
Stellae Fixae | Copper | 29 | Pre–16th-century alchemical symbol. | |
♀ | Venus | Copper | 29 | Alchemical symbol. |
Copper | Copper | 29 | Alchemical symbol. | |
© | Copper | Copper | 29 | Daltonian symbol circa 1808. |
Arsenic | Arsenic | 33 | Alchemical symbol. | |
🜺 | Arsenic | Arsenic | 33 | Alchemical symbol. |
☽ | Luna | Silver | 47 | Alchemical symbol. |
🜛 | Silver | Silver | 47 | Alchemical symbol. |
♃ | Iupiter | Tin | 50 | Alchemical symbol. |
♁ | Antimony | Antimony | 51 | Alchemical symbol. |
Antimony | Antimony | 51 | Alchemical symbol. | |
☾ | Platinum | Platinum | 78 | Alchemical symbol. |
☉ | Platinum | Platinum | 78 | Alchemical symbol. |
Uranus | Platinum | 78 | Alchemical symbol. | |
☼ | Sol | Gold | 79 | Alchemical symbol from the 16th century. |
Sol | Gold | 79 | Alchemical symbol from 1700 through 1783. | |
🜚 | Gold | Gold | 79 | Alchemical symbol. |
Pisces | Mercury | 80 | Pre–16th-century alchemical symbol. | |
Neptunus | Mercury | 80 | Alchemical symbol from the 17th century. | |
☿ | Mercurius | Mercury | 80 | Alchemical symbol from 1700 through 1783. |
♄ | Saturnus | Lead | 82 | Alchemical symbol circa 1783. |
Taurus | Bismuth | 83 | Alchemical symbol. |
Symbols for named isotopes
The following is a list of isotopes of elements given in the previous tables which have been designated unique symbols. By this it is meant that a comprehensive list of current systematic symbols (in the uAtom form) are not included in the list and can instead be found in the Isotope index chart. The symbols for the named isotopes of hydrogen, deuterium (D) and tritium (T) are still in use today. Heavy water and other deuterated solvents are commonly used in chemistry, and it is convenient to use a single character rather than a symbol with a subscript in these cases. The practice also continues with tritium compounds. When the name of the solvent is given, a lowercase d is sometimes used. For example, d6-benzene and C6D6 can be used instead of [2H6]C6H6.[3]
The symbols for isotopes of elements other than hydrogen are no longer in use within the scientific community. Many of these symbols were designated during the early years of radiochemistry, and several isotopes (namely those in the actinium decay family, the radium decay family, and the thorium decay family) bear placeholder names using the early naming system devised by Ernest Rutherford.[4]
Chemical symbol | Name | Atomic number | Origin of symbol |
---|---|---|---|
Ac | Actinium | 89 | From the Greek aktinos. Name restricted at one time to 227Ac, an isotope of actinium. This named isotope later became the official name for element 89. |
AcA | Actinium A | 84 | From actinium and A. Placeholder name given at one time to 215Po, an isotope of polonium identified in the decay chain of actinium. |
AcB | Actinium B | 82 | From actinium and B. Placeholder name given at one time to 211Pb, an isotope of lead identified in the decay chain of actinium. |
AcC | Actinium C | 83 | From actinium and C. Placeholder name given at one time to 211Bi, an isotope of bismuth identified in the decay chain of actinium. |
AcC' | Actinium C' | 84 | From actinium and C'. Placeholder name given at one time to 211Po, an isotope of polonium identified in the decay chain of actinium. |
AcC" | Actinium C" | 81 | From actinium and C". Placeholder name given at one time to 207Tl, an isotope of thallium identified in the decay chain of actinium. |
AcK | Actinium K | 87 | Name given at one time to 223Fr, an isotope of francium identified in the decay chain of actinium. |
AcU | Actino-uranium | 92 | Name given at one time to 235U, an isotope of uranium. |
AcX | Actinium X | 88 | Name given at one time to 223Ra, an isotope of radium identified in the decay chain of actinium. |
An | Actinon | 86 | From actinium and emanation. Name given at one time to 219Rn, an isotope of radon identified in the decay chain of actinium. |
D | Deuterium | 1 | From the Greek deuteros. Name given to 2H. |
Io | Ionium | 90 | Name given at one time to 230Th, an isotope of thorium identified in the decay chain of uranium. |
MsTh1 | Mesothorium 1 | 88 | Name given at one time to 228Ra, an isotope of radium. |
MsTh2 | Mesothorium 2 | 89 | Name given at one time to 228Ac, an isotope of actinium. |
Pa | Protactinium | 91 | From the Greek protos and actinium. Name restricted at one time to 231Pa, an isotope of protactinium. This named isotope later became the official name for element 91. |
Ra | Radium | 88 | From the Latin radius. Name restricted at one time to 226Ra, an isotope of radium. This named isotope later became the official name for element 88. |
RaA | Radium A | 84 | From radium and A. Placeholder name given at one time to 218Po, an isotope of polonium identified in the decay chain of radium. |
RaB | Radium B | 82 | From radium and B. Placeholder name given at one time to 214Pb, an isotope of lead identified in the decay chain of radium. |
RaC | Radium C | 83 | From radium and C. Placeholder name given at one time to 214Bi, an isotope of bismuth identified in the decay chain of radium. |
RaC' | Radium C' | 84 | From radium and C'. Placeholder name given at one time to 214Po, an isotope of polonium identified in the decay chain of radium. |
RaC" | Radium C" | 81 | From radium and C". Placeholder name given at one time to 210Tl, an isotope of thallium identified in the decay chain of radium. |
RaD | Radium D | 82 | From radium and D. Placeholder name given at one time to 210Pb, an isotope of lead identified in the decay chain of radium. |
RaE | Radium E | 83 | From radium and E. Placeholder name given at one time to 210Bi, an isotope of bismuth identified in the decay chain of radium. |
RaE" | Radium E" | 81 | From radium and E". Placeholder name given at one time to 206Tl, an isotope of thallium identified in the decay chain of radium. |
RaF | Radium F | 84 | From radium and F. Placeholder name given at one time to 210Po, an isotope of polonium identified in the decay chain of radium. |
RdAc | Radioactinium | 90 | Name given at one time to 227Th, an isotope of thorium. |
RdTh | Radiothorium | 90 | Name given at one time to 228Th, an isotope of thorium. |
Rn | Radon | 86 | From radium and emanation. Name restricted at one time to 222Rn, an isotope of radon identified in the decay chain of radium. This named isotope later became the official name for element 86 in 1923. |
T | Tritium | 1 | From the Greek tritos. Name given to 3H. |
Th | Thorium | 90 | After Thor. Name restricted at one time to 232Th, an isotope of thorium. This named isotope later became the official name for element 90. |
ThA | Thorium A | 84 | From thorium and A. Placeholder name given at one time to 216Po, an isotope of polonium identified in the decay chain of thorium. |
ThB | Thorium B | 82 | From thorium and B. Placeholder name given at one time to 212Pb, an isotope of lead identified in the decay chain of thorium. |
ThC | Thorium C | 83 | From thorium and C. Placeholder name given at one time to 212Bi, an isotope of bismuth identified in the decay chain of thorium. |
ThC' | Thorium C' | 84 | From thorium and C'. Placeholder name given at one time to 212Po, an isotope of polonium identified in the decay chain of thorium. |
ThC" | Thorium C" | 81 | From thorium and C". Placeholder name given at one time to 208Tl, an isotope of thallium identified in the decay chain of thorium. |
ThX | Thorium X | 88 | Name given at one time to 224Ra, an isotope of radium identified in the decay chain of thorium. |
Tn | Thoron | 86 | From thorium and emanation. Name given at one time to 220Rn, an isotope of radon identified in the decay chain of thorium. |
UI | Uranium I | 92 | Name given at one time to 238U, an isotope of uranium. |
UII | Uranium II | 92 | Name given at one time to 234U, an isotope of uranium. |
UX1 | Uranium X1 | 90 | Name given at one time to 234Th, an isotope of thorium identified in the decay chain of uranium. |
UX2 | Uranium X2 | 91 | Name given at one time to 234Pa, an isotope of protactinium identified in the decay chain of uranium. |
UY | Uranium Y | 90 | Name given at one time to 231Th, an isotope of thorium identified in the decay chain of uranium. |
UZ | Uranium Z | 91 | Name given at one time to 234Pa, an isotope of protactinium identified in the decay chain of uranium. |
Other symbols
This section needs expansion with: aminoacid symbols. You can help by adding to it. (January 2013) |
General:
- E: any element or electrophile
- M: metal – any metal atom
- Mu: muonium
- Nu: any nucleophile
- Pn: protonium
- Ps: positronium
- St: steel (occasionally used)
- X: halogen – any halogen atom
From organic chemistry:
- Ac: acetyl – (also used for the element actinium: see above)
- Ad: adamantyl
- Ak: alkyl
- Ar: aryl – (also used for the element argon: see above)
- Bn: benzyl
- Bu: butyl
- Bz: benzoyl – (also used for berzelium, an old suggested name for praseodymium).
- Cp: cyclopentadienyl
- Cy: cyclohexyl
- Et: ethyl
- i-Pr: isopropyl
- Me: methyl
- Mes: mesityl (2,3,6-trimethylphenyl)
- Ms: mesyl (methylsulfonyl)
- Np: neopentyl - (also used for the element neptunium: see above)
- Ph: phenyl
- Pr: propyl – (also used for the element praseodymium: see above)
- R: radical – some unspecified element or radical
- t-Bu: tert-butyl
- Tf: triflyl (trifluoromethanesulfonyl)
- Tr: trityl (triphenylmethyl)
- Ts: tosyl
From inorganic chemistry:
- Ab: albite
- Cy: cyanide - obsolete symbol for CN group in inorganic cyanides, cyanogen, etc.
- Di: didymium – rare earth metal that proved to be a mixture of the elements praseodymium and neodymium.
- Dp: decipium – rare earth metal that proved to be a mixture of the elements samarium, neodymium and praseodymium.
- Pp: philippium – rare earth metal that proved to be a mixture of the elements holmium and samarium.
See also
Notes
- ^ This should not be confused with formula. When a number is present at the bottom right corner of the symbol of the element, only then is it said to be a formula, but if the number is not present, it is a symbol.
- ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak 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 atomic mass given.
- ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am The isotopic composition of this element varies in some geological specimens, and the variation may exceed the uncertainty stated in the table.
- ^ a b c d e f g h i j k l m n o The isotopic composition varies in terrestrial material such that a more precise atomic weight can not be given.
- ^ a b c d e f g h The isotopic composition of the element can vary in commercial materials, which can cause the atomic weight to deviate significantly from the given value.
- ^ 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.
- ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at Name changed due to a standardization of, modernization of, or update to older formerly-used symbol.
- ^ a b c d e f g h i j k l m n o Name designated by discredited/disputed claimant.
- ^ a b c d e f g h i j k l m n o p q r s t u v w x Name proposed prior to discovery/creation of element or prior to official re-naming of a placeholder name.
- ^ a b c d e f g h i j k l m n o p q r s Temporary placeholder name.
References
- ^ The interstellar medium, with definition of HI and HII regions
- ^ Praseodymium
- ^ IUPAC. "Isotopically Modified Compounds". IUPAC. Retrieved 31 March 2015.
- ^ Morgan, G.T., ed. (1905). "Annual Reports on the Progress of Chemistry for 1904". Journal of the Chemical Society. 1. Gurney & Jackson: 268.
In view of the extraordinarily complex nature of the later changes occurring in Radium, Rutherford has proposed a new and convenient system of nomenclature. The first product of the change of the radium emanation is named radium A, the next radium B, and so on.
- Element name etymologies. Retrieved July 15, 2005.
- Atomic Weights of the Elements 2001, Pure Appl. Chem. 75(8), 1107–1122, 2003. Retrieved June 30, 2005. Atomic weights of elements with atomic numbers from 1–109 taken from this source.
- IUPAC Standard Atomic Weights Revised (2005).
- WebElements Periodic Table. Retrieved June 30, 2005. Atomic weights of elements with atomic numbers 110–116 taken from this source.
- Lapp, Ralph E. Matter. Life Science Library. New York: Time, Inc. 1963.
- Leighton, Robert B. Principles of Modern Physics. New York: McGraw-Hill. 1959.
- Scerri, E.R. "The Periodic Table, Its Story and Its Significance". New York, Oxford University Press. 2007.