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The periodic table of the elements

The periodic table is an arrangment of the chemical elements ordered by atomic number so that periodic properties of the elements (chemical periodicity) are made clear.

Explore the thermochemistry and thermodynamics of the chemical elements through this periodic table

Group 1 2   3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Period
1
1
1.008
Hydrogen
2
4.0026
Helium
2
3
6.94
Lithium
4
9.0122
Beryllium
5
10.81
Boron
6
12.011
Carbon
7
14.007
Nitrogen
8
15.999
Oxygen
9
18.998
Fluorine
10
20.180
Neon
3
11
22.990
Sodium
12
24.305
Magnesium
13
26.982
Aluminium
14
28.085
Silicon
15
30.974
Phosphorus
16
S
32.06
Sulfur
17
35.45
Chlorine
18
39.948
Argon
4
19
39.098
Potassium
20
40.078
Calcium
21
44.956
Scandium
22
47.867
Titanium
23
50.942
Vanadium
24
51.996
Chromium
25
54.938
Manganese
26
55.845
Iron
27
58.933
Cobalt
28
58.693
Nickel
29
63.546
Copper
30
65.38
Zinc
31
69.723
Gallium
32
72.630
Germanium
33
74.922
Arsenic
34
78.971
Selenium
35
79.904
Bromine
36
83.798
Krypton
5
37
85.468
Rubidium
38
87.62
Strontium
39
88.906
Yttrium
40
91.224
Zirconium
41
92.906
Niobium
42
95.95
Molybdenum
43
Tc
98
Technetium
44
101.07
Ruthenium
45
102.91
Rhodium
46
106.42
Palladium
47
107.87
Silver
48
112.41
Cadmium
49
114.82
Indium
50
118.71
Tin
51
121.76
Antimony
52
127.60
Tellurium
53
126.90
Iodine
54
131.29
Xenon
6
55
132.91
Caesium
56
137.33
Barium
*
71
174.97
Lutetium
72
178.49
Hafnium
73
180.95
Tantalum
74
183.84
Tungsten
75
186.21
Rhenium
76
190.23
Osmium
77
192.22
Iridium
78
195.08
Platinum
79
196.97
Gold
80
200.59
Mercury
81
204.38
Thallium
82
207.2
Lead
83
208.98
Bismuth
84
Po
209
Polonium
85
At
210
Astatine
86
Rn
222
Radon
7
87
Fr
223
Francium
88
Ra
226
Radium
**
103
Lr
262
Lawrencium
104
Rf
267
Rutherfordium
105
Db
270
Dubnium
106
Sg
269
Seaborgium
107
Bh
270
Bohrium
108
Hs
269
Hassium
109
Mt
278
Meitnerium
110
Ds
281
Darmstadtium
111
Rg
281
Roentgenium
112
Cn
285
Copernicium
113
Nh
286
Nihonium
114
Fl
289
Flerovium
115
Mc
289
Moscovium
116
Lv
293
Livermorium
117
Ts
293
Tennessine
118
Og
294
Oganesson
 
*Lanthanoids *
57
138.91
Lanthanum
58
140.12
Cerium
59
140.91
Praseodymium
60
144.24
Neodymium
61
Pm
145
Promethium
62
150.36
Samarium
63
151.96
Europium
64
157.25
Gadolinium
65
158.93
Terbium
66
162.50
Dysprosium
67
164.93
Holmium
68
167.26
Erbium
69
168.93
Thulium
70
173.05
Ytterbium
**Actinoids **
89
Ac
227
Actinium
90
Th
232.04
Thorium
91
Pa
231.04
Protactinium
92
U
238.03
Uranium
93
Np
237
Neptunium
94
Pu
244
Plutonium
95
Am
243
Americium
96
Cm
247
Curium
97
Bk
247
Berkelium
98
Cf
251
Californium
99
Es
252
Einsteinium
100
Fm
257
Fermium
101
Md
258
Mendelevium
102
No
259
Nobelium

The standard form of the periodic table shown here includes periods (shown horizontally) and groups (shown vertically). The properties of elements in groups are similar in some respects to each other.

There is no one single or best structure for the periodic table but by whatever consensus there is, the form used here is very useful and the most common. The periodic table is a masterpiece of organised chemical information and the evolution of chemistry's periodic table into the current form is an astonishing achievement.