GROUP
1
PERIOD
1
1
H
Hydrogen
1.008
3
2
4
Be
11
12
Sodium
22.99
Magnesium
24.31
19
20
6
7
Beryllium
9.012
Na Mg
3
Non-metals
Alkaline Earth Metals
Halogens
Transition Metals
Noble Gases
Other Metals
Lanthanides
Metalloids
Actinides
4
21
22
25
8
26
10
Co
Ni
28
B
14
6
C
15
7
N
16
8
Fluorine
19.00
F
Ne
13
14
15
16
17
18
Si
Silicon
28.09
Phosphorus
30.97
Sulfur
32.06
Chlorine
35.45
Cl
Ar
30
31
32
33
34
35
Copper
63.55
Zinc
65.39
Gallium
69.72
Germanium
72.64
Arsenic
74.92
Selenium
78.96
Br
36
Bromine
79.90
Kr
49
50
51
52
53
54
29
12
Aluminium
26.98
Iron
55.85
37
38
39
40
41
42
43
44
45
46
47
48
Niobium
92.91
Molybdenum
95.96
Technetium
(98)
Ruthenium
101.1
Rhodium
102.9
Palladium
106.4
Silver
107.9
Cadmium
112.4
73
74
75
76
77
78
79
80
Rhenium
186.2
Osmium
190.2
Iridium
192.2
Platinum
195.1
Gold
197.0
Mercury
200.5
Thallium
204.38
Tl
Pb
Lead
207.2
Bismuth
209.0
Bi
Po
114
115
116
55
56
Caesium
132.9
Barium
137.3
87
88
Cs Ba
Fr
Ra
(223)
(226)
Francium
Radium
Y
Zr
Zirconium
91.22
72
Hf
57-71
Lanthanides
89-103
Nb Mo Tc
Ta
W
Cu Zn Ga Ge As
S
Ru Rh Pd Ag Cd
Re Os
Ir
Pt
Au Hg
Te
Tin
118.7
Antimony
121.8
Tellurium
127.6
Iodine
126.9
I
Xe
81
82
83
84
85
86
Astatine
(210)
Radon
(222)
117
118
Oganesson
104
105
106
107
108
109
110
111
112
113
Dubnium
Seaborgium
Bohrium
Hassium
Meitnerium
Darmstadtium
Roentgenium
Copernicium
Nihonium
Flerovium
Moscovium
Livermorium
Tennessine
59
60
61
62
63
64
65
66
67
68
69
70
71
Erbium
167.3
Thulium
168.9
Ytterbium
173.0
Lutetium
175.0
103
57
58
(265)
Db Sg Bh Hs Mt Ds Rg Cn Nh
(268)
(270)
(277)
(276)
(281)
(280)
(285)
(284)
Nd Pm Sm Eu Gd Tb Dy Ho
(289)
Mc
(288)
Lv
(293)
La
Ce
Cerium
140.1
Praseodymium
140.9
Neodymium
144.2
Promethium
(145)
Samarium
150.4
Europium
152.0
Gadolinium
157.2
Terbium
158.9
Dysprosium
162.5
Holmium
164.9
89
90
91
92
93
94
95
96
97
98
99
100
101
102
Actinium
(227)
Thorium
232.0
Neptunium
(237)
Plutonium
(244)
Americium
(243)
Curium
(247)
Berkelium
(247)
Einsteinium
(252)
Fermium
(257)
Mendelevium
(258)
Nobelium
(259)
Lanthanum
138.9
Ac Th
American Chemical Society
Pr
(271)
Fl
Polonium
(209)
Pa
Protactinium
231.0
U
Uranium
238.0
Np Pu Am Cm Bk
Cf
Californium
(251)
Er Tm Yb
Es Fm Md No
Xenon
131.3
At Rn
Tungsten
183.9
Rf
Krypton
83.79
Sn
Tantalum
180.9
Rutherfordium
Argon
39.95
In
Indium
114.8
Sb
Se
Hafnium
178.5
Actinides
Neon
20.18
Al
11
Manganese
54.94
Yttrium
88.91
10
Oxygen
16.00
Chromium
52.00
Nickel
58.69
Helium
4.003
Nitrogen
14.01
Vanadium
50.94
Cobalt
58.93
9
He
Carbon
12.01
P
O
17
Boron
10.81
Titanium
47.88
Sr
Cr Mn Fe
5
Name
Average Atomic Mass
9
27
13
Scandium
44.96
Strontium
87.62
V
24
7
Symbol
Calcium
40.08
Rubidium
85.47
Ti
23
6
Platinum
195.1
2
Ca
Rb
Sc
5
Pt
18
Atomic Number
K
Potassium
39.10
5
4
Li
Lithium
6.94
3
2
78
Alkali Metals
Ts Og
(294)
(294)
Lu
Lr
Lawrencium
(262)
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