Elements table - alphabetical list

The following table gives the atomic mass of the most abundant or most stable isotope for each element, together with a few others. They are listed in alphabetical order. The percentage abundance or decay mode and half life are also listed.

Name	Symbol	Proton number	Nucleon number	Atomic mass (u)	Half life	% or decay mode
Actinium	Ac	89	227	227.027 81	22 years	a
Aluminium	Al	13	27	26.981 635
Americium	Am	95	243	243.061 38	8x103 years	a
Antimony	Sb	51	121	120.903		57.25
Argon	Ar	18	40	39.962 384		95.0
Arsenic	As	33	75	74.921
Astatine	At	85	210	209.987	8.3 hours	a
Barium	Ba	56	138	137.905 0		71.66
Barium	Ba	56	139	138.908 6	85 mins	b-
Barium	Ba	56	140	139.910 5	12.8 days	b-
Berkelium	Bk	97	247	247.070 18	104 years	a
Beryllium	Be	4	8	8.005 308	~6x10-17s	2a
Beryllium	Be	4	9	9.012 186		100
Bismuth	Bi	83	209	208.980 42		100
Bismuth	Bi	83	210	209.984 11	3x106 years	a
Boron	B	5	11	11.009 305		80.4
Bromine	Br	35	79	78.918 4		50.54
Bromine	Br	35	81	80.916 3		49.46
Bromine	Br	35	85	84.938		50.54
Cadmium	Cd	48	114	113.903 6
Caesium	Cs	55	133	132.905 1
Caesium	Cs	55	137	136.9068	28 years	b-
Californium	Cf	98	249	249.075 70	360 years	a
Carbon	C	6	11	11.011 43	20.5 mins	b+
Carbon	C	6	12	12.000 000		98.89
Carbon	C	6	14	14.003 242	5570 years	b-
Calcium	Ca	20	40	39.962 59		96.97
Calcium	Ca	20	45	44.956 19	165 days	b-
Calcium	Ca	20	47	46.954 5	4.7 days	b-
Cerium	Ce	58	140	139.905 3
Chlorine	Cl	17	35	34.968 85
Cobalt	Co	27	59	58.933 19		100
Cobalt	Co	27	60	59.933 81	5.29 years	g
Chromium	Cr	24	52	51.940 51
Copper	Cu	29	63	62.929 59		69.1
Curium	Cm	96	245	245.065 34	104 years	a
Curium	Cm	96	248	Fission	5x105 years
Deuterium	D	1	2	2.014 102
Dysprosium	Dy	66	164	163.938 4
Einsteinium	Es	99	253	253.084 68	20 days	a
Electron	e	0	0	0.000 548
Erbium	Er	68	166	165.930 4
Europium	Eu	63	151	150.919 6
Fermium	Fm	100	250	250.079 48	30 mins	a
Fluorine	F	9	19	18.998 40		100
Francium	Fr	87	223	223.019 8	22 mins	b-
Gadolinium	Gd	64	158	157.924 1
Gallium	Ga	31	69	68.925 7
Germanium	Ge	32	74	73.921 2
Gold	Au	79	197	196.966 55		100
Gold	Au	79	198	197.968 24	2.7 days	b-
Hafnium	Hf	72	180	179.946 8
Helium	He	2	3	3.016 030
Helium	He	2	4	4.002 604		~100
Helium	He	2	5	5.012 224	7.6x10-22s	n
Holmium	Ho	67	165	164.930 3
Hydrogen	H	1	1	1.007 825		99.985
Hydrogen	H	1	2	2.014 102
Hydrogen	H	1	3	3.016 049	12.3 years	b-
Indium	In	49	113	112.904 3
Indium	In	49	115	114.904 1	6x1014 years	b-
Iodine	I	53	127	126.904 35		100
Iodine	I	53	128	127.905 83	25 mins	b-
Iodine	I	53	131	130.906 13	8.04 days	b-
Iodine	I	53	132	131.907 997	138 mins	b-
Iridium	Ir	77	193	192.963 3
Iron	Fe	26	54	53.939 62		5.82
Iron	Fe	26	56	55.934 93		91.66
Iron	Fe	26	57	56.935 39		2.19
Krypton	Kr	36	84	83.911 50		49.46
Lanthanum	La	57	139	138.906 1		99.91
Lanthanum	La	57	148	147.961
Lawrencium	Lw	103	257	257.099 8	~35 s	a
Lead	Pb	82	206	205.974 46	47 days	24.1
Lead	Pb	82	208	207.976 44		52.3
Lead	Pb	82	209	208.981 0	3.3 hours	b-
Lithium	Li	3	7	7.016 005		92.58
Lutetium	Lu	71	175	174.940 9
Magnesium	Mg	12	24	23.985 045		78.7
Manganese	Mn	25	55	54.938 88
Mendelevium	Md	101	255	255.090 6	30 mins	a
Mercury	Hg	80	200	199.968 34		23.1
Mercury	Hg	80	202	201.970 63		29.8
Mercury	Hg	80	203	202.972 85	47 days	b-
Molybdenum	Mo	42	98	97.906
Neodymium	Nd	60	142	141.907 5
Neptunium	Np	93	237	237.048 03	2.2x106 years	a
Neon	Ne	10	20	19.992 440		90.51
Neon	Ne	10	22	21.991 384		9.22
Neutron	n	1	1	1.008 665	15 mins (free)	b-
Nickel	Ni	28	58	57.935 34		100
Niobium	Nb	41	93	92.906 0
Nitrogen	N	7	13	13.005 739	10.1 mins	b+
Nitrogen	N	7	14	14.003 074		99.63
Nobelium	No	102	255	255.093 3	3.1 mins	a
Osmium	Os	76	190	189.958 3		26.4
Osmium	Os	76	192	191.161 4		41.0
Oxygen	O	8	15	15.003 066	122 s	b+
Oxygen	O	8	16	15.994 915		99.76
Palladium	Pd	46	106	105.9036
Phosphorus	P	15	31	30.973 763
Phosphorus	P	15	32	31.973 908	14.5 days	b-
Platinum	Pt	78	194	193.962 8		32.9
Platinum	Pt	78	195	194.964 82		33.8
Plutonium	Pu	94	242	242.058 7	3.8x105 years	a
Polonium	Po	84	209	208.982 46	200 years	a
Polonium	Po	84	210	209.982 87	138 days	a
Potassium	K	19	39	38.963 71		93.26
Potassium	K	19	40	39.964 01	1.28x109 years	b-
Potassium	K	19	41	38.963 71
Potassium	K	19	42	41.962 4	12.5 hours	b-
Praseodymium	Pr	59	141	140.907 4
Promethium	Pm	61	147	146.914 9	2.6 years	b-
Protoactinium	Pa	91	231	231.035 94	3.4x104 years	a
Protoactinium	Pa	91	233	233.040 11	27.4 days	b-
Proton	p	1	1	1.007 276
Radon	Rn	86	220	220.011 4	52 s	a
Radon	Rn	86	222	222.017	3.83 days	a
Radium	Ra	88	226	226.025 36	1600 years	a
Radium	Ra	88	228	228.031 07	1.6x103 years	a
Rhenium	Re	75	185	184.953
Rhodium	Rh	45	103	102.904 8
Rubidium	Rb	37	85	84.911 7
Ruthenium	Ru	44	102	101.903 7
Samarium	Sm	62	152	151.919 5
Scandium	Sc	21	45	44.995 92
Selenium	Se	34	80	79.916 51
Silicon	Si	14	28	27.976 93
Silver	Ag	47	107	106.905		54.1
Silver	Ag	47	111	110.905 2	7.5 days	b-
Sodium	Na	11	23	22.989 773		100
Sodium	Na	11	24	23.990 97	15 hours	b-
Strontium	Sr	38	88	87.905 6		82.6
Strontium	Sr	38	89	88.907	51 days	b-
Strontium	Sr	38	90	84.911 7	28 days	b-
Sulphur	S	16	32	31.927 072		95.0
Tantalum	Ta	73	181	180.940 8
Technetium	Tc	43	99	98.906 *	6 hours	g
Technetium	Tc	43	101	100.9059
Tellurium	Te	52	122	121.903
Terbium	Tb	65	159	158.925 0
Thallium	Tl	81	205	204.974 46		70.5
Thorium	Th	90	232	232.038 21	1.41x1010 years	a
Thulium	Tm	69	169	168.934
Titanium	Ti	22	48	47.947 95
Tin	Sn	50	120	119.902
Tritium	T	1	3	3.016 049	12.3 years	b-
Tungsten	W	74	184	183.951 0
Uranium	U	92	235	235.043 9	7.1x108 years	a
Uranium	U	92	238	238.050 7	4.5x109 years	a
Vanadium	V	23	51	50.943 98
Xenon	Xe	54	129	128.904 779		26.44
Xenon	Xe	54	132	131.904 16		26.89
Xenon	Xe	54	133	132.905 6	5.3 days	b-
Ytterbium	Yb	70	174	173.939 0
Yttrium	Y	39	89	88.905
Zinc	Zn	30	64	63.929 15		48.89
Zirconium	Zr	40	90	89.904 3

For a list of the elements in nucleon number order please see: Table of elements (nucleon number order)