The periodic table
www.webelements.com
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
Hydrogen
Helium
1
2
H
He
Key:
1.008
Lithium
Beryllium
Element Name
Boron
Carbon
Nitrogen
Oxygen
Fluorine
4.0026
Neon
3
4
Atomic number
5
6
7
8
9
10
Li
Be
Symbol
B
6.94
Sodium
9.0122
Magnesium
Atomic weight (mean relative mass)
11
12
22.990
Potassium
24.305
Calcium
Scandium
Titanium
Vanadium
Chromium
Manganese
Iron
Cobalt
Nickel
Copper
19
20
21
22
23
24
25
26
27
28
Na Mg
K
40.078(4)
Strontium
Ca
Sc
44.956
Yttrium
47.867
Zirconium
50.942
Niobium
51.996
Molybdenum
54.938
Technetium
55.845(2)
Ruthenium
37
38
39
40
41
42
43
Sr
85.468
Caesium
87.62
Barium
55
56
Cs
Ba
87
88
132.91
Francium
Fr
[223.02]
137.33
Radium
Ra
[226.03]
12.011
Silicon
14.007
Phosphorus
15.999
Sulfur
18.998
Chlorine
F
Ne
13
14
15
16
17
18
Al
39.098
Rubidium
Rb
10.81
Aluminium
Y
57-70
*
89-102
**
Cr Mn Fe
Ni
S
Cl
20.180
Argon
Ar
Zinc
26.982
Gallium
28.085
Germanium
30.974
Arsenic
32.06
Selenium
35.45
Bromine
39.948
Krypton
29
30
31
32
33
34
35
36
58.933
Rhodium
58.693
Palladium
63.546(3)
Silver
Cu Zn Ga Ge
65.38(2)
Cadmium
69.723
Indium
72.63
Tin
74.922
Antimony
Se
78.96(3)
Tellurium
Br
79.904
Iodine
83.798(2)
Xenon
44
45
46
47
48
49
50
51
52
53
54
[97.91]
Rhenium
101.07(2)
Osmium
102.91
Iridium
106.42
Platinum
107.87
Gold
112.41
Mercury
114.82
Thallium
In
Sn
Sb
121.76
Bismuth
127.60(3)
Polonium
126.90
Astatine
I
Xe
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
186.21
Bohrium
190.23(2)
Hassium
192.22
Meitnerium
107
108
109
Hf
103
104
Lr
Ta
W
180.95
Dubnium
183.84
Seaborgium
105
106
[268.13]
[271.13]
Re Os
Ir
[262.11]
[265.12]
Rf
Db Sg
Bh
Hs
Mt
Lanthanum
Cerium
Praseodymium Neodymium
Promethium
Samarium
Europium
La
Ce
140.12
Thorium
140.91
Protactinium
89
90
91
Ac
[227.03]
58
Th
232.04
59
Pr
Pa
231.04
60
[270]
61
[277.15]
62
[276.15]
63
Pt
Au Hg
195.08
196.97
Darmstadtium Roentgenium
Tl
118.71
Lead
Pb
Bi
Te
Kr
95.96(2)
Tungsten
174.97
178.49(2)
Lawrencium Rutherfordium
Ru Rh Pd Ag Cd
As
92.906(2)
Tantalum
Lu
Nb Mo Tc
Co
P
O
91.224(2)
Hafnium
138.91
Actinium
**actinoids
Zr
V
Si
N
88.906
Lutetium
57
*lanthanoids
Ti
C
Po
204.38
Ununtrium
207.2
Flerovium
208.98
Ununpentium
[208.98]
Livermorium
[209.99]
Ununseptium
[222.02]
Ununoctium
114
115
116
117
118
[294]
[294]
111
112
113
[281.16]
[280.16]
[285.17]
[284.18]
[289.19]
[288.19]
[293]
Gadolinium
Terbium
Dysprosium
Holmium
Erbium
Thulium
Ytterbium
Dy Ho
Er
Ds Rg Cn Uut
65
Nd Pm Sm Eu Gd Tb
66
67
Fl Uup Lv Uus Uuo
68
69
70
Tm Yb
144.24
Uranium
[144.91]
Neptunium
150.36(2)
Plutonium
151.96
Americium
157.25(3)
Curium
158.93
Berkelium
162.50
Californium
164.93
Einsteinium
167.26
Fermium
168.93
Mendelevium
173.05
Nobelium
92
93
94
95
96
97
98
99
100
101
102
[237.05]
[244.06]
[243.06]
[247.07]
[247.07]
[252.08]
[257.10]
[258.10]
[259.10]
U
238.03
Np Pu Am Cm Bk
Rn
200.59
Copernicium
110
64
At
131.29
Radon
Cf
[251.08]
Es Fm Md No
Symbols and names: the symbols and names of the elements, and their spellings are those recommended by the International Union of Pure and Applied Chemistry (IUPAC - http://www.iupac.org/). Names have yet to be proposed for elements 113, 115, 117, and 118 and so those used
here are IUPAC’s temporary systematic names. In some countries, the spellings aluminum, cesium, and sulphur are usual.
Group labels: the numeric system (1–18) used here is the current IUPAC convention.
Atomic weights (mean relative masses): these are the IUPAC 2009 values and given to 5 significant figures. The last significant figure of each value is considered reliable to ±1 except where a larger uncertainty is given in parentheses. Representative values for those elements having an
atomic weight interval are given (H, Li, B, C, N, O, Si, S, Cl, Tl). Elements for which the atomic weight is given within [brackets] have no stable nuclides and are represented by the element’s longest lived isotope reported in the IUPAC 2009 values.
©2012 Dr Mark J Winter [WebElements Ltd and University of Sheffield]. All rights reserved. For updates to this table see http://www.webelements.com/nexus/Printable_Periodic_Table (Version date: 7 June 2012).