Period
Hydrogen & alkali metals
Alkaline earth metals
Triels
Tetrels
Pnictogens
Chalcogens
Halogens
Noble gases
1
Hydrogen
1
H
1.007
Helium
2
He
4.002
2
Lithium
3
Li
6.941
Beryllium
4
Be
9.012
Boron
5
B
10.811
Carbon
6
C
12.011
Nitrogen
7
N
14.007
Oxygen
8
O
15.999
Fluorine
9
F
18.998
Neon
10
Ne
20.18
3
Sodium
11
Na
22.99
Magnesium
12
Mg
24.305
Aluminum
13
Al
26.982
Silicon
14
Si
28.086
Phosphorus
15
P
30.974
Sulfur
16
S
32.065
Chlorine
17
Cl
35.453
Argon
18
Ar
39.948
4
Potassium
19
K
39.098
Calcium
20
Ca
40.078
Scandium
21
Sc
44.956
Titanium
22
Ti
47.867
Vanadium
23
V
50.942
Chromium
24
Cr
51.996
Manganese
25
Mn
54.938
Iron
26
Fe
55.845
Cobalt
27
Co
58.933
Nickel
28
Ni
58.693
Copper
29
Cu
63.546
Zinc
30
Zn
65.38
Gallium
31
Ga
69.723
Germanium
32
Ge
72.64
Arsenic
33
As
74.922
Selenium
34
Se
78.96
Bromine
35
Br
79.904
Krypton
36
Kr
83.798
5
Rubidium
37
Rb
85.468
Strontium
38
Sr
87.62
Yttrium
39
Y
88.906
Zirconium
40
Zr
91.224
Niobium
41
Nb
92.906
Molybdenum
42
Mo
95.96
Technetium
43
Tc
98
Ruthenium
44
Ru
101.07
Rhodium
45
Rh
102.906
Palladium
46
Pd
106.42
Silver
47
Ag
107.868
Cadmium
48
Cd
112.411
Indium
49
In
114.818
Tin
50
Sn
118.71
Antimony
51
Sb
121.76
Tellurium
52
Te
127.6
Iodine
53
I
126.904
Xenon
54
Xe
131.293
6
Cesium
55
Cs
132.905
Barium
56
Ba
137.327
Lanthanum
57
La
138.905
Cerium
58
Ce
140.116
Praseodymium
59
Pr
140.908
Neodymium
60
Nd
144.242
Promethium
61
Pm
145
Samarium
62
Sm
150.36
Europium
63
Eu
151.964
Gadolinium
64
Gd
157.25
Terbium
65
Tb
158.925
Dysprosium
66
Dy
162.5
Holmium
67
Ho
164.93
Erbium
68
Er
167.259
Thulium
69
Tm
168.934
Ytterbium
70
Yb
173.054
Lutetium
71
Lu
174.967
Hafnium
72
Hf
178.49
Tantalum
73
Ta
180.948
Wolfram
74
W
183.84
Rhenium
75
Re
186.207
Osmium
76
Os
190.23
Iridium
77
Ir
192.217
Platinum
78
Pt
195.084
Gold
79
Au
196.967
Mercury
80
Hg
200.59
Thallium
81
Tl
204.383
Lead
82
Pb
207.2
Bismuth
83
Bi
208.98
Polonium
84
Po
210
Astatine
85
At
210
Radon
86
Rn
222
7
Francium
87
Fr
223
Radium
88
Ra
226
Actinium
89
Ac
227
Thorium
90
Th
232.038
Protactinium
91
Pa
231.036
Uranium
92
U
238.029
Neptunium
93
Np
237
Plutonium
94
Pu
244
Americium
95
Am
243
Curium
96
Cm
247
Berkelium
97
Bk
247
Californium
98
Cf
251
Einsteinium
99
Es
252
Fermium
100
Fm
257
Mendelevium
101
Md
258
Nobelium
102
No
259
Lawrencium
103
Lr
262
Rutherfordium
104
Rf
261
Dubnium
105
Db
262
Seaborgium
106
Sg
266
Bohrium
107
Bh
264
Hassium
108
Hs
267
Meitnerium
109
Mt
268
Darmstadtium
110
Ds
271
Roentgenium
111
Rg
272
Copernicium
112
Cn
285
Nihonium
113
Nh
284
Flerovium
114
Fl
289
Moscovium
115
Mc
288
Livermorium
116
Lv
292
Tennessine
117
Ts
295
Oganesson
118
Og
294