1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
2
He
Helium
4.0026
3
4
5
6
7
8
9
10
11
12
10
Ne
Neon
20.180
3
4
5
6
7
8
9
10
11
12
18
Ar
Argon
39.948
36
Kr
Krypton
83.798
54
Xe
Xeon
131.29
57-71
86
Rn
Radon
222
89-103
109
Mt
Meitnerium
278
110
Ds
Darmstadtium
281
111
Rg
Roentgenium
282
113
Nh
Copernicium
286
115
Mc
Moscovium
290
116
Lv
Livermorium
293
117
Ts
Tennessine
294
118
Og
Oganesson
295
Fr
Hydrogen
1.008
Ra
Hydrogen
1.008
3
57
La
Lanthanum
138.905
58
Ce
Cerium
140.12
59
Pr
Praseodymium
140.907
60
Nd
Neodymium
144.242
61
Pm
Promethium
145
62
Sm
Samarium
150.36
63
Eu
Europium
151.964
64
Gd
Gadolinium
157.25
65
Tb
Terbium
158.925
66
Dy
Dysprosium
162.500
67
Ho
Holmium
164.930
68
Er
Erbium
167.259
69
Tm
Thulium
168.934
70
Yb
Ytterbium
173.045
71
Lu
Lutetium
174.968
Fr
Actinium
227
Hide
Hydrogen
1.008
3
89
Ac
Actinium
227
90
Th
Thorium
232.04
91
Pa
Protactinium
231.031
92
U
Uranium
238.028
93
Np
Neptunium
237
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
266