Protons, neutrons and electrons

Composition of the neutral atom: protons and electrons equal the atomic number Z; the neutron count N = A − Z is given for the explicitly selected isotope with mass number A.

Data completeness Protons 118 of 118Electrons 118 of 118Selected isotope 118 of 118Mass number A 118 of 118Neutrons 118 of 118

Showing 118 of 118 elements

	Symbol	Name
1	H	Hydrogen	1	1	H-1	1	0
2	He	Helium	2	2	He-4	4	2
3	Li	Lithium	3	3	Li-7	7	4
4	Be	Beryllium	4	4	Be-9	9	5
5	B	Boron	5	5	B-11	11	6
6	C	Carbon	6	6	C-12	12	6
7	N	Nitrogen	7	7	N-14	14	7
8	O	Oxygen	8	8	O-16	16	8
9	F	Fluorine	9	9	F-19	19	10
10	Ne	Neon	10	10	Ne-20	20	10
11	Na	Sodium	11	11	Na-23	23	12
12	Mg	Magnesium	12	12	Mg-24	24	12
13	Al	Aluminum	13	13	Al-27	27	14
14	Si	Silicon	14	14	Si-28	28	14
15	P	Phosphorus	15	15	P-31	31	16
16	S	Sulfur	16	16	S-32	32	16
17	Cl	Chlorine	17	17	Cl-35	35	18
18	Ar	Argon	18	18	Ar-40	40	22
19	K	Potassium	19	19	K-39	39	20
20	Ca	Calcium	20	20	Ca-40	40	20
21	Sc	Scandium	21	21	Sc-45	45	24
22	Ti	Titanium	22	22	Ti-48	48	26
23	V	Vanadium	23	23	V-51	51	28
24	Cr	Chromium	24	24	Cr-52	52	28
25	Mn	Manganese	25	25	Mn-55	55	30
26	Fe	Iron	26	26	Fe-56	56	30
27	Co	Cobalt	27	27	Co-59	59	32
28	Ni	Nickel	28	28	Ni-58	58	30
29	Cu	Copper	29	29	Cu-63	63	34
30	Zn	Zinc	30	30	Zn-64	64	34
31	Ga	Gallium	31	31	Ga-69	69	38
32	Ge	Germanium	32	32	Ge-74	74	42
33	As	Arsenic	33	33	As-75	75	42
34	Se	Selenium	34	34	Se-80	80	46
35	Br	Bromine	35	35	Br-79	79	44
36	Kr	Krypton	36	36	Kr-84	84	48
37	Rb	Rubidium	37	37	Rb-85	85	48
38	Sr	Strontium	38	38	Sr-88	88	50
39	Y	Yttrium	39	39	Y-89	89	50
40	Zr	Zirconium	40	40	Zr-90	90	50
41	Nb	Niobium	41	41	Nb-93	93	52
42	Mo	Molybdenum	42	42	Mo-98	98	56
43	Tc	Technetium	43	43	Tc-98	98	55
44	Ru	Ruthenium	44	44	Ru-102	102	58
45	Rh	Rhodium	45	45	Rh-103	103	58
46	Pd	Palladium	46	46	Pd-106	106	60
47	Ag	Silver	47	47	Ag-107	107	60
48	Cd	Cadmium	48	48	Cd-114	114	66
49	In	Indium	49	49	In-115	115	66
50	Sn	Tin	50	50	Sn-120	120	70
51	Sb	Antimony	51	51	Sb-121	121	70
52	Te	Tellurium	52	52	Te-130	130	78
53	I	Iodine	53	53	I-127	127	74
54	Xe	Xenon	54	54	Xe-132	132	78
55	Cs	Cesium	55	55	Cs-133	133	78
56	Ba	Barium	56	56	Ba-138	138	82
57	La	Lanthanum	57	57	La-139	139	82
58	Ce	Cerium	58	58	Ce-140	140	82
59	Pr	Praseodymium	59	59	Pr-141	141	82
60	Nd	Neodymium	60	60	Nd-142	142	82
61	Pm	Promethium	61	61	Pm-145	145	84
62	Sm	Samarium	62	62	Sm-152	152	90
63	Eu	Europium	63	63	Eu-153	153	90
64	Gd	Gadolinium	64	64	Gd-158	158	94
65	Tb	Terbium	65	65	Tb-159	159	94
66	Dy	Dysprosium	66	66	Dy-164	164	98
67	Ho	Holmium	67	67	Ho-165	165	98
68	Er	Erbium	68	68	Er-166	166	98
69	Tm	Thulium	69	69	Tm-169	169	100
70	Yb	Ytterbium	70	70	Yb-174	174	104
71	Lu	Lutetium	71	71	Lu-175	175	104
72	Hf	Hafnium	72	72	Hf-180	180	108
73	Ta	Tantalum	73	73	Ta-181	181	108
74	W	Tungsten	74	74	W-184	184	110
75	Re	Rhenium	75	75	Re-187	187	112
76	Os	Osmium	76	76	Os-192	192	116
77	Ir	Iridium	77	77	Ir-193	193	116
78	Pt	Platinum	78	78	Pt-195	195	117
79	Au	Gold	79	79	Au-197	197	118
80	Hg	Mercury	80	80	Hg-202	202	122
81	Tl	Thallium	81	81	Tl-205	205	124
82	Pb	Lead	82	82	Pb-208	208	126
83	Bi	Bismuth	83	83	Bi-209	209	126
84	Po	Polonium	84	84	Po-209	209	125
85	At	Astatine	85	85	At-210	210	125
86	Rn	Radon	86	86	Rn-222	222	136
87	Fr	Francium	87	87	Fr-223	223	136
88	Ra	Radium	88	88	Ra-226	226	138
89	Ac	Actinium	89	89	Ac-227	227	138
90	Th	Thorium	90	90	Th-232	232	142
91	Pa	Protactinium	91	91	Pa-231	231	140
92	U	Uranium	92	92	U-238	238	146
93	Np	Neptunium	93	93	Np-237	237	144
94	Pu	Plutonium	94	94	Pu-244	244	150
95	Am	Americium	95	95	Am-243	243	148
96	Cm	Curium	96	96	Cm-247	247	151
97	Bk	Berkelium	97	97	Bk-247	247	150
98	Cf	Californium	98	98	Cf-251	251	153
99	Es	Einsteinium	99	99	Es-252	252	153
100	Fm	Fermium	100	100	Fm-257	257	157
101	Md	Mendelevium	101	101	Md-258	258	157
102	No	Nobelium	102	102	No-259	259	157
103	Lr	Lawrencium	103	103	Lr-262	262	159
104	Rf	Rutherfordium	104	104	Rf-267	267	163
105	Db	Dubnium	105	105	Db-268	268	163
106	Sg	Seaborgium	106	106	Sg-271	271	165
107	Bh	Bohrium	107	107	Bh-270	270	163
108	Hs	Hassium	108	108	Hs-270	270	162
109	Mt	Meitnerium	109	109	Mt-278	278	169
110	Ds	Darmstadtium	110	110	Ds-281	281	171
111	Rg	Roentgenium	111	111	Rg-282	282	171
112	Cn	Copernicium	112	112	Cn-285	285	173
113	Nh	Nihonium	113	113	Nh-286	286	173
114	Fl	Flerovium	114	114	Fl-289	289	175
115	Mc	Moscovium	115	115	Mc-289	289	174
116	Lv	Livermorium	116	116	Lv-293	293	177
117	Ts	Tennessine	117	117	Ts-294	294	177
118	Og	Oganesson	118	118	Og-294	294	176

Sources and notes

Neutrons are never derived by rounding the standard atomic weight — only from the mass number of the selected isotope.