Elements and Solar System Abundances

		Name	Atomic Weight	Abundance			Name	Atomic Weight	Abundance
1	H	hydrogen	1.01	12.00	57	La	lanthanum	138.91	1.20
2	He	helium	4.00	10.99	58	Ce	cerium	140.12	1.61
3	Li	lithium	6.94	1.16	59	Pr	praseodymium	140.91	0.78
4	Be	beryllium	9.01	1.15	60	Nd	neodymium	144.24	1.47
5	B	boron	10.81	2.6	61	Pm	promethium	(145)
6	C	carbon	12.01	8.55	62	Sm	samarium	150.36	0.97
7	N	nitrogen	14.01	7.97	63	Eu	europium	151.97	0.54
8	O	oxygen	16.00	8.87	64	Gd	gadolinium	157.25	1.07
9	F	fluorine	19.00	4.56	65	Tb	terbium	158.93	0.33
10	Ne	neon	20.18	8.08	66	Dy	dysprosium	162.50	1.15
11	Na	sodium	22.99	6.31	67	Ho	holmium	164.93	0.50
12	Mg	magnesium	24.31	7.58	68	Er	erbium	167.26	0.95
13	Al	aluminum	26.98	6.48	69	Tm	thulium	168.93	0.13
14	Si	silicon	28.09	7.55	70	Yb	ytterbium	173.04	0.95
15	P	phosphorus	30.97	5.57	71	Lu	lutetium	174.97	0.12
16	S	sulfur	32.07	7.27	72	Hf	hafnium	178.49	0.73
17	Cl	chlorine	35.45	5.27	73	Ta	tantalum	180.95	0.13
18	Ar	argon	39.94	—	74	W	tungsten	183.85	0.68
19	K	potassium	39.10	5.13	75	Re	rhenium	186.21	0.27
20	Ca	calcium	40.08	6.34	76	Os	osmium	190.2	1.38
21	Sc	scandium	44.96	3.09	77	Ir	iridium	192.22	1.37
22	Ti	titanium	47.88	4.93	78	Pt	platinum	195.08	1.68
23	V	vanadium	50.94	4.02	79	Au	gold	196.97	0.83
24	Cr	chromium	52.00	5.68	80	Hg	mercury	200.59	1.09
25	Mn	manganese	54.94	5.53	81	Tl	thallium	204.38	0.82
26	Fe	iron	55.85	7.51	82	Pb	lead	207.2	2.05
27	Co	cobalt	58.93	4.91	83	Bi	bismuth	208.98	0.71
28	Ni	nickel	58.69	6.25	84	Po	polonium	(209)
29	Cu	copper	63.55	4.27	85	At	astatine	(210)
30	Zn	zinc	65.39	4.65	86	Rn	radon	(222)
31	Ga	gallium	69.72	3.13	87	Fr	fancium	(223)
32	Ge	germanium	72.61	3.63	88	Ra	radium	(226)
33	As	arsenic	74.92	2.37	89	Ac	actinium	(227)
34	Se	selenium	78.96	3.35	90	Th	thorium	232.04
35	Br	bromine	79.90	2.63	91	Pa	protractinium	231.04	0.08
36	Kr	krypton	83.80	3.23	92	U	uranium	238.03
37	Rb	rubidium	85.47	2.40	93	Np	neptunium	(237)	-0.47
38	Sr	strontium	87.62	2.93	94	Pu	plutonium	(244)
39	Y	yttrium	88.91	2.22	95	Am	americium	(243)
40	Zr	zirconium	91.22	2.61	96	Cm	curium	(247)
41	Nb	niobium	92.91	1.40	97	Bk	berkelium	(247)
42	Mo	molybdenum	95.94	1.96	98	Cf	californium	(251)
43	Tc	technetium	(98)		99	Es	einsteinium	(252)
44	Ru	ruthenium	101.07	1.82	100	Fm	fermium	(257)
45	Rh	rhodium	102.91	1.09	101	Md	mendelevium	(260)
46	Pd	palladium	106.42	1.70	102	No	nobelium	(259)
47	Ag	silver	107.87	1.24	103	Lr	lawrencium	(262)
48	Cd	cadmium	112.41	1.76	104	Rf	rutherfordium	(261)
49	In	indium	114.82	0.82	105	Db	dubnium	(262)
50	Sn	tin	118.71	2.14	106	Sg	seaborgium	(266)
51	Sb	antimony	121.75	1.04	107	Bh	bohrium	(264)
52	Te	tellurium	127.60	2.24	108	Hs	hassium	(267)
53	I	iodine	126.90	1.51	109	Mt	meitnerium	(268)
54	Xe	xenon	131.29	2.23	110			(269)
55	Cs	cesium	132.91	1.12	111			(272)
56	B	barium	137.33	2.21	112			(277)

Abundances given are logarithmic, based on hydrogen = 12.00.

The abundances given are solar photospheric for elements 3-10 and meteoritic for other elements; when both are available, differences are almost always slight. The abundance data were supplied by Nicolas Grevesse in 1994, and represent and update form Edward Anders and Nicolas Grevesse, Geochimica et Cosmochima Acta, 53, 197-214 (1989).

Atomic weights are from the 1998 IUPAC (International union of Pure and Applied Chemistry) report, plus the longest halflife for the heaviest elements. In 1997, a committee of the International Union of Pure and Applied Chemistry recommended the names given for elements 101 through 109.

I thank Peter Armbruster of Gesellschaft für Schwerionen forschung mbH Darmstad for information about the heaviest elements, many of which he discovered.