The Periodic Table of the Elements
1
I A
   Legend  
18
VIII A
1
H
Hydrogen
1.00794(7)
 
2
II A
Alkali metals
Alkali earth metals
Transition metals
Lanthanides
Actinides
Main group metals
Metalloids
Nonmetals
Halogens
Noble gases
 
13
III A
 
14
IV A
 
15
V A
 
16
VI A
 
17
VII A
2
He
Helium
4.002602(2)
3
Li
Lithium
6.941(2)
4
Be
Berillium
9.012182(3)
  
Atomic number
Symbol
Name
Atomic mass
  
5
B
Boron
10.811(7)
6
C
Carbon
12.0107(8)
7
N
Nitrogen
14.0067(2)
8
O
Oxygen
15.9994(3)
9
F
Fluorine
18.9984032(5)
10
Ne
Neon
20.1797(6)
11
Na
Sodium
22.98976928(2)
12
Mg
Magnesium
24.3050(6)
 
3
III B
 
4
IV B
 
5
V B
 
6
VI B
 
7
VII B
 
8
┌───
 
9
VIII B
 
10
───┐
 
11
I B
 
12
II B
13
Al
Aluminum
26.9815386(8)
14
Si
Silicon
28.0855(3)
15
P
Phosphorus
30.973762(2)
16
S
Sulfur
32.065(5)
17
Cl
Chlorine
35.453(2)
18
Ar
Argon
39.948(1)
19
K
Potassium
39.0983(1)
20
Ca
Calcium
40.078(4)
21
Sc
Scandium
44.955912(6)
22
Ti
Titanium
47.867(1)
23
V
Vanadium
50.9415(1)
24
Cr
Chromium
51.9961(6)
25
Mn
Manganese
54.938045(5)
26
Fe
Iron
55.845(2)
27
Co
Cobalt
58.933195(5)
28
Ni
Nickel
58.6934(4)
29
Cu
Copper
63.546(3)
30
Zn
Zinc
65.38(2)
31
Ga
Gallium
69.723(1)
32
Ge
Germanium
72.64(1)
33
As
Arsenic
74.92160(2)
34
Se
Selenium
78.96(3)
35
Br
Bromine
79.904(1)
36
Kr
Krypton
83.798(2)
37
Rb
Rubidium
85.4678(3)
38
Sr
Strontium
87.62(1)
39
Y
Yttrium
88.90585(2)
40
Zr
Zirconium
91.224(2)
41
Nb
Niobium
92.90638(2)
42
Mo
Molybdenum
95.96(2)
43
Tc
Technetium
(98)
44
Ru
Ruthenium
101.07(2)
45
Rh
Rhodium
102.90550(2)
46
Pd
Palladium
106.42(1)
47
Ag
Silver
107.8682(2)
48
Cd
Cadmium
112.411(8)
49
In
Indium
114.818(3)
50
Sn
Tin
118.710(7)
51
Sb
Antimony
121.760(1)
52
Te
Tellurium
127.60(3)
53
I
Iodine
126.90447(3)
54
Xe
Xenon
131.293(6)
55
Cs
Cesium
132.9054519(2)
56
Ba
Barium
137.327(7)
57
La
Lanthanum
138.90547(7)
72
Hf
Hafnium
178.49(2)
73
Ta
Tantalum
180.94788(2)
74
W
Tungsten
183.84(1)
75
Re
Rhenium
186.207(1)
76
Os
Osmium
190.23(3)
77
Ir
Iridium
192.217(3)
78
Pt
Platinum
195.084(9)
79
Au
Gold
196.966569(4)
80
Hg
Mercury
200.59(2)
81
Tl
Thallium
204.3833(2)
82
Pb
Lead
207.2(1)
83
Bi
Bismuth
208.98040(1)
84
Po
Polonium
(209)
85
At
Astatine
(210)
86
Rn
Radon
(222)
87
Fr
Francium
(223)
88
Ra
Radium
(226)
89
Ac
Actinium
(227)
104
Rf
Rutherfordium
(261)
105
Db
Dubnium
(262)
106
Sg
Seaborgium
(266)
107
Bh
Bohrium
(264)
108
Hs
Hassium
(277)
109
Mt
Meitnerium
(268)
110
Ds
Darmstadtium
(271)
111
Rg
Roentgenium
(272)
   
 
58
Ce
Cerium
140.116(1)
59
Pr
Praseodymium
140.90765(2)
60
Nd
Neodymium
144.242(3)
61
Pm
Promethium
(145)
62
Sm
Samarium
150.36(2)
63
Eu
Europium
151.964(1)
64
Gd
Gadolinium
157.25(3)
65
Tb
Terbium
158.92535(2)
66
Dy
Dysprosium
162.500(1)
67
Ho
Holmium
164.93032(2)
68
Er
Erbium
167.259(3)
69
Tm
Thulium
168.93421(2)
70
Yb
Ytterbium
173.054(5)
71
Lu
Lutetium
174.9668(1)
 
90
Th
Thorium
232.03806(2)
91
Pa
Protactinium
231.03588(2)
92
U
Uranium
238.02891(3)
93
Np
Neptunium
(237)
94
Pu
Plutonium
(244)
95
Am
Americium
(243)
96
Cm
Curium
(247)
97
Bk
Berkelium
(247)
98
Cf
Californium
(251)
99
Es
Einsteinium
(252)
100
Fm
Fermium
(257)
101
Md
Mendelevium
(258)
102
No
Nobelium
(259)
103
Lr
Lawrencium
(262)
© 2005-2008 Daniel C. Tofan (site design)

Notes:
Atomic masses according to the latest data published by IUPAC: http://www.chem.qmul.ac.uk/iupac/AtWt/. Digits in parantheses represent the uncertainty in the last digit.
Individual element pages are no longer available.