Periodic Table of the Elements
Group 1
1.00794
Atomic Mass
+1
-1
Mass numbers in parenthesis are those of the
most stable or most common isotope
H
Symbol
Atomic Number
Electron Configuration
1
1s1
2
Hydrogen
6.941
28.0855
Si
-4
+2
+4
Selected Oxidation States
He
14
13
Name
+2
14
10.81
15
+3 12.01
Li
Be
B
C
3
4
5
6
1s22s2
Lithium
22.98977
+1 24.305
Transition Elements
+2
26.98154
Mg
Al
11
12
13
2
2
[Ne]3s
[Ne]3s
Sodium
39.0983
Magnesium
+1 40.08
3
+2 44.9559
4
+3 47.88
K
Ca
Sc
Ti
19
20
21
22
[Ar]4s1
[Ar]4s2
Potassium
85.4678
[Ar]3d14s2
Calcium
+1 87.62
6
V
+2 51.996
+3
+4
+5
Cr
23
[Ar]3d24s2
Scandium
+2 88.9059
5
+2 50.9415
+3
+4
7
Mn
24
[Ar]3d34s2
8
+2 54.9380
+3
+6
[Ar]3d54s2
+4 92.9064
+3 95.94
+5
+3 (98)
+6
Rb
Sr
Y
Zr
Nb
Mo
Tc
37
38
39
40
41
42
43
[Kr]5s1
[Kr]5s2
[Kr]4d15s2
Rubidium Strontium
132.905
+1 137.33
[Kr]4d25s2
Yttrium
+2 138.906
[Kr]4d45s1
[Kr]4d55s1
+4 180.948
+5 183.85
+6 186.207
Ba
La
Hf
Ta
W
Re
55
56
57
72
73
74
75
[Xe]6s2
Cesium
(223)
[Xe]5d16s2
+2 227.028
Ga
Ge
As
30
31
32
33
Iron
+4 101.07
+6
+7
Cobalt
+3 102.906
Nickel
+3 106.42
+2 121.75
+4
Pd
Ag
Cd
In
Sn
Sb
45
46
47
48
49
50
51
[Kr]4d105s0
+4 190.2
+6
+7
+3 192.22
+4
+3 195.08
+4
[Kr]4d105s1
Silver
+2 196.967
+4
[Kr]4d105s2
[Ne]3s23p6
[Ne]3s 3p
Chlorine
-2 79.904
+4
+6
Br
Argon
-1 83.80
+1
+5
0
+2
Kr
35
36
Selenium
-3 127.60
+3
+5
Te
Bromine
-2 127.60
+4
+6
I
52
Krypton
-1 131.29
+1
+5
+7
Xe
53
0
+2
+4
+6
54
[Kr]4d105s25p1 [Kr]4d105s25p2 [Kr]4d105s25p3 [Kr]4d105s25p4 [Kr]4d105s25p5 [Kr]4d105s25p6
Cadmium
+1 200.59
+3
5
Indium
+1 204.383
+2
Tin
Antimony Tellurium
+1 207.2
+3
+2 208.980
+4
+3 (209)
+5
Iodine
Xenon
+2 (210)
+4
(222)
0
Os
Ir
Pt
Au
Hg
Tl
Pb
Bi
Po
At
Rn
76
77
78
79
80
81
82
83
84
85
86
+3 (261)
Tantalum
(262)
Tungsten
(263)
Rhenium
(262)
Osmium
(265)
Iridium
(266)
Platinum
Gold
(269)
(272?)
Ac
Rf
Db
Sg
Bh
Hs
Mt
Ds
89
104
105
106
107
108
109
110
Radium
+3 118.71
Rh
[Kr]4d85s1
Se
18
2
Sulfur
-3 78.96
+3
+5
Gallium Germanium Arsenic
+2 114.82
44
[Kr]4d75s1
Ar
17
[Ar]3d104s24p1 [Ar]3d104s24p2 [Ar]3d104s24p3 [Ar]3d104s24p4 [Ar]3d104s24p5 [Ar]3d104s24p6
Zinc
+1 112.41
-1 39.948
+1
+3
+5
+7
Cl
4
34
Ru
88
Francium
[Ar]3d104s2
Copper
+2 107.868
+4
Ra
[Rn]6d17s2
+2 74.9216
+4
Zn
[Ar]3d104s1
S
[Ne]3s 3p
Phosphorus
Silicon
+3 72.59
Ne
-2 35.453
+4
+6
2
[Ne]3s 3p
29
87
[Rn]7s2
[Ne]3s 3p
Cu
[Ar]3d84s2
0
3
28
[Ar]3d74s2
-3 32.06
+3
+5
F
16
2
Ni
Fr
[Rn]7s1
+2 69.72
0
15
2
Helium
-3 15.9994
-2 18.998403 -1 20.179
-2
-1
+1
+2
8
9
10
+3
2 2
4
1s22s22p5
1s22s22p6
+4 1s 2s 2p
+5 Oxygen
Fluorine
Neon
[Xe]4f145d26s2 [Xe]4f145d36s2 [Xe]4f145d46s2 [Xe]4f145d56s2 [Xe]4f145d66s2 [Xe]4f145d76s2 [Xe]4f145d96s1 [Xe]4f145d106s1 [Xe]4f145d106s2 [Xe]4f145d106s26p1 [Xe]4f145d106s26p2 [Xe]4f145d106s26p3 [Xe]4f145d106s26p4 [Xe]4f145d106s26p5 [Xe]4f145d106s26p6
Barium Lanthanum Hafnium
+1 226.025
2
Aluminum
+1 65.39
+2
P
14
27
Zirconium Niobium MolybdenumTechnetium Ruthenium Rhodium Palladium
+3 178.49
Cs
[Xe]6s1
+2 63.546
+3
Si
1
Co
[Ar]3d64s2
[Kr]4d65s1
+2 58.69
+3
-4 30.97376
+2
+4
26
Titanium Vanadium Chromium Manganese
+3 91.224
10
+2 58.9332
+3
+3 28.0855
[Ne]3s 3p
12
1s22s22p3
Carbon Nitrogen
1s2
17
O
7
Fe
25
[Ar]3d54s1
9
+2 55.847
+3
+4
+7
11
N
1s22s22p2
Boron
Na
1
P
E
R
I
O
D
1s22s22p1
Beryllium
16
-4 14.0067
+2
+4
Metals
1s22s1
2
Nonmetals
[Ne]3s23p2
Silicon
+1 9.01218
18
4.00260
Mercury
Thallium
Lead
Bismuth
Polonium
Astatine
Radon
(277?)
Uuu Uub
111
112
[Rn]5f146d26s2 [Rn]5f146d37s2 [Rn]5f146d47s2 [Rn]5f146d57s2 [Rn]5f146d67s2 [Rn]5f146d77s2 [Rn]5f146d87s2
Actinum Rutherfordium Dubnium Seaborgium Bohrium
140.12
Lanthanoid Series
+3 140.908
+4
Ce
58
1
1
2
[Xe]4f 5d 6s
+3 144.24
Hassium Meitnerium Dormstadtium Unununium Ununbium
+4 (145)
+3 150.36
+2 151.96
+3
+2 157.25
+3
+3 158.925
Pr
Nd
Pm
Sm
Eu
Gd
59
60
61
62
63
64
3
2
4
[Xe]4f 6s
2
5
[Xe]4f 6s
2
6
[Xe]4f 6s
2
[Xe]4f 6s
7
2
7
[Xe]4f 6s
1
2
[Xe]4f 5d 6s
+3 162.50
+3 164.930
+3 167.26
Actinoid Series
+4 231.036
+4 238.029
+5
+3 237.048
+4
+5
+6
Th
Pa
U
90
91
92
93
[Rn]5f26d17s2
[Rn]5f36d17s2
[Rn]5f46d17s2
[Rn]6d27s2
Np
+3 (244)
+4
+5
+6
Pu
94
[Rn]5f67s2
+3 (243)
+4
+5
+6
Am
+3 (247)
+4
+5
+6
95
[Rn]5f77s2
Thorium Protactinium Uranium Neptunium Plutonium Americium
+3 173.04
+2 174.967
+3
Tb
Dy
Ho
Er
Tm
Yb
65
66
67
68
69
70
9
2
[Xe]4f 6s
10
2
[Xe]4f 6s
11
2
[Xe]4f 6s
Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium
232.038
+3 168.934
+3 (247)
+3 (251)
+4
+3 (252)
12
2
[Xe]4f 6s
Erbium
(257)
13
2
[Xe]4f 6s
Thulium
(258)
14
[Xe]4f 6s
Ytterbium
(259)
Bk
Cf
Es
Fm
Md
No
96
97
98
99
100
101
102
Curium
[Rn]5f97s2
[Rn]5f107s2
[Rn]5f117s2
[Rn]5f127s2
[Rn]5f137s2
Lu
71
2
Cm
[Rn]5f76d17s2
+3
[Rn]5f147s2
[Xe]4f145d16s2
Lutetium
(260)
Lr
103
[Rn]5f146d17s2
Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium