Chemical Symbols

Chemical Symbols 

the abbreviated designation, by letters, of the chemical elements.

Modern chemical symbols (see Table 1.) consist of the first

Table 1. Symbols, names, atomic numbers, and atomic weights of chemical elements
Symbol	Latin name	English name	Atomic number	Atomic weight
1 The not generally adopted symbols and names of the elements with atomic numbers 102 and 103 are given in parentheses 2 Atomic weights are given according to the carbon scale (the atomic weight of the carbon isotope 12 C is exactly 12), corresponding to the 1971 International Table; the mass numbers of the longest-lived isotopes of radioactive elements are given in brackets
Ac	Actinium	Actinium	89	[227]
Ag	Argentum	Silver	47	107.8680
Al	Aluminium	Aluminum	13	26.98154
Am	Americium	Americium	95	[243]
Ar	Argonum	Argon	18	39.948
As	Arsenicum	Arsenic	33	74.9216
At	Astatium	Astatine	85	[210]
Au	Aurum	Gold	79	196.9665
B	Borum	Boron	5	10.810
Ba	Baryum	Barium	56	137.34
Be	Beryllium	Beryllium	4	9.01218
Bi	Bismuthum	Bismuth	83	208.9804
Bk	Berkelium	Berkelium	97	[247]
Br	Bromum	Bromine	35	79.904
C	Carboneum	Carbon	6	12.011
Ca	Calcium	Calcium	20	40.08
Cd	Cadmium	Cadmium	48	112.40
Ce	Cerium	Cerium	58	140.12
Cf	Californium	Californium	98	[251]
Cl	Chlorum	Chlorine	17	35.453
Cm	Curium	Curium	96	[247]
Co	Cobaltum	Cobalt	27	58.9332
Cr	Chromium	Chromium	24	51.996
Cs	Caesium	Cesium	55	132.9054
Cu	Cuprum	Copper	29	63.546
Dy	Dysprosium	Dysprosium	66	162.50
Er	Erbium	Erbium	68	167.26
Es	Esteinium	Einsteinium	99	[254]
Eu	Europium	Europium	63	151.96
F	Fluorum	Fluorine	9	18.99840
Fe	Ferrum	Iron	26	55.847
Fm	Fermium	Fermium	100	[257]
Fr	Francium	Francium	87	[223]
Ga	Gallium	Gallium	31	69.72
Gd	Gadolinium	Gadolinium	64	157.25
Ge	Germanium	Germanium	32	72.59
H	Hydrogenium	Hydrogen	1	1.0079
He	Helium	Helium	2	4.00260
Hf	Hafnium	Hafnium	72	178.49
Hg	Hydrargyrum	Mercury	80	200.59
Ho	Holmium	Holmium	67	164.9304
1	lodum	Iodine	53	126.9045
I n	Indium	Indium	49	114.82
r I	Iridium	Iridium	77	192.22
K	Kalium	Potassium	19	39.098
Kr	Kryptonum	Krypton	36	83.80
Ku	Kurtschatovium	Kurchatovium	104	[261]
La	Lanthanum	Lanthanum	57	138.9055
Li	Lithium	Lithium	3	6.941
(Lr)	(Lawrencium)	(Lawrencium)	103	[256]
Lu	Lutetium	Lutetium	71	174.97
Md	Mendelevium	Mendelevium	101	[258]
Mg	Magnesiom	Magnesium	12	24.305
Mn	Manganum	Manganese	25	54.9380
Mo	Molybdaenum	Molybdenum	42	95.94
N	Nitrogenium	Nitrogen	7	14.0067
Na	Natrium	Sodium	11	22.98977
Nb	Niobium	Niobium	41	92.9064
Nd	Neodymium	Neodymium	60	144.24
Ne	Neonum	Neon	10	20.179
Ni	Niccolum	Nickel	28	58.71
(No)	(Nobelium)	(Nobelium)	102	[255]
Np	Neptunium	Neptunium	93	237.0482
0	Oxygenium	Oxygen	8	15.9994
Os	Osmium	Osmium	76	190.2
P	Phosphorus	Phosphorus	15	30.97376
Pa	Protactinium	Protactinium	91	231.0359
Pb	Plumbum	Lead	82	207.2
Pd	Palladium	Palladium	46	106.4
Pm	Promethium	Promethium	61	[145]
Po	Polonium	Polonium	84	[209]
Pr	Praseodymium	Praseodymium	59	140.9077
Pt	Platinum	Platinum	78	195.09
Pu	Plutonium	Plutonium	94	[244]
Ra	Radium	Radium	88	226.0254
Rb	Rubidium	Rubidium	37	85.4678
Re	Rhenium	Rhenium	75	186.2
Rh	Rhodium	Rhodium	45	102.9055
Rn	Radonum	Radon	86	[222]
Ru	Ruthenium	Ruthenium	44	101.07
S	Sulphur	Sulfur	16	32.06
Sb	Stibium	Antimony	51	121.75
Sc	Scandium	Scandium	21	44.9559
Se	Selenium	Selenium	34	78.96
Si	Silicium	Silicon	14	28.086
Sm	Samarium	Samarium	62	150.4
Sn	Stannum	Tin	50	188.69
Sr	Strontium	Strontium	38	87.62
Ta	Tantalum	Tantalum	73	180.949
Tb	Terbium	Terbium	65	158.9254
Tc	Technetium	Technetium	43	98.9062
Te	Tellurium	Tellurium	52	127.60
Th	Thorium	Thorium	90	232.0381
Ti	Titanium	Titanium	22	47.90
Tl	Thallium	Thallium	81	204.37
Tm	Thulium	Thulium	69	168.9342
U	Uranium	Uranium	92	238.029
V	Vanadium	Vanadium	23	50.94
W	Wolframium	Tungsten	74	183.85
Xe	Xenonum	Xenon	54	131.30
Y	Yttrium	Yttrium	39	88.9059
Yb	Ytterbium	Ytterbium	70	173.04
Zn	Zincum	Zinc	30	65.38
Zr	Zirconium	Zirconium	40	91.22

letter or the first and one of the subsequent letters of the Latin name of the elements. In chemical formulas and chemical equations each chemical symbol expresses the relative weight (the atomic weight) in addition to the name of the element. The mass number is written at the upper left (sometimes upper right) of the chemical symbol to denote isobars and isotopes. The atomic number is written at the lower left. To denote the ion rather than the neutral atom, the ionic charge is written at the upper right. The number of atoms in a molecule of a given element is indicated at the lower right. For example, is a single-charged ion of a chlorine isotope (atomic number, 17; mass number, 35); is the diatomic molecule of the same isotope. The isobars of argon and calcium are denoted by and , respectively. The chemical symbols given in the table are international, but in some countries, symbols derived from the local names of the elements are used as well. For example, in France, instead of N for nitrogen, Be for beryllium, and W for tungsten, Az (azote), Gl (glucinium), and Tu (tungstene), respectively, have been adopted. In the United States, Cb (columbium) is often used in place of the symbol for niobium, Nb. The names and symbols for the elements with atomic numbers 102 and 103 (nobelium and lawrencium) have not yet been generally adopted.

Chemists of the ancient world and the Middle Ages used symbolic representations, letter abbreviations, and combinations of both (see Figure 1) to designate substances, chemical

Figure 1. Several chemical symbols of the 18th century (from J. C. P. Ehrchsleben, Nachal’nye osnovaniia khimii; translated from German to [Old] Russian by N. Sokolov, St. Petersburg, 1788, pp. 16–17). The sign for copper should be inverted (misprint in the original).

operations, and instruments. Seven metals of antiquity were represented by the astronomical signs of the seven celestial bodies: sun (gold), moon (silver), Jupiter (tin), Venus (copper), Saturn (lead), Mercury (mercury), and Mars (iron). Metals discovered between the 15th and the 18th century— bismuth, zinc, and cobalt—were designated by the first letters of their names. The symbol for ethyl alcohol (Latin, spiritus vini) consisted of the letters S and ∇. The symbols for nitric acid (Latin, aquafortis) and aqua regia (Latin, aqua regia’, a mixture of hydrochloric and nitric acids) consisted of the symbol for water V and capitals F and R, respectively. The symbol for glass (Latin, vitrum) was formed of two V’s, one inverted.

Attempts to systematize the old chemical symbols continued to the end of the 18th century. At the beginning of the 19th century the English chemist J. Dalton proposed that atoms of the chemical elements be designated by circles containing dots, dashes, the initial letters of the English names of metals, and so on. Dalton’s chemical symbols gained some acceptance in Great Britain and Western Europe, but they were soon displaced by the purely letter symbols proposed by the Swedish chemist J. J. Berzelius in 1814. The principles he advanced for formulating chemical symbols remain in effect to the present day. The first published report in Russia on Berzelius’ chemical symbols was made in 1824 by Moscow physician I. la. Zatsepin.

REFERENCES

Lomonosov, M. V. Poln. sobr. soch., vol. 2. Moscow-Leningrad, 1951. Pages 706–09.
Giua, M. Istoriia khimii. Moscow, 1966. (Translated from Italian.)
Crosland, M. P. Historical Studies in the Language of Chemistry. London, 1962.

S. A. POGODIN