2
He
Helium
4.0026
5
B
Boron
10.0811
10
Ne
Neon
20.180
14
Si
Silicon
28.086
18
Ar
Argon
39.948
32
Ge
Germanium
72.640
33
As
Arsenic
74.922
36
Kr
Krypton
83.798
51
Sb
Antimony
121.76
52
Te
Tellurium
127.60
54
Xe
Xenon
131.29
57
La
Lanthanum
138.91
58
Ce
Cerium
44.956
59
Pr
Praseodymium
140.91
60
Nd
Neodymium
144.24
61
Pm
Promethium
145
62
Sm
Samarium
150.36
63
Eu
Europium
151.96
64
Gd
Gadolinium
157.25
65
Tb
Terbium
158.93
66
Dy
Dysprosium
162.5
67
Ho
Scandium
44.956
68
Er
Erbium
167.26
69
Tm
Thulium
168.93
70
Yb
Ytterbium
173.04
71
Lu
Lutetium
174.97
86
Rn
Radon
222
89
Ac
Actinium
227
90
Th
Thorium
232.04
91
Pa
Protactinium
231.04
92
U
Uranium
238.03
93
Np
Neptunium
237.05
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
109
Mt
Meitnerium
44.956
110
Ds
Darmstadtium
44.956
111
Rg
Roentgenium
282
112
Cn
Copernicium
44.956
113
Nh
Nihonium
286
114
Fl
Flerovium
289
115
Mc
Moscovium
289
116
Lv
Livermorium
293
117
Ts
Tennessine
118
Og
Oganesson
294