IUPAC Periodic Table of the Elements
1
18
2
1
He
H
helium
hydrogen
1.0080
± 0.0002
3
Li
2
lithium
beryllium
9.0122
± 0.0001
11
Na
magnesium
24.305
± 0.002
20
Ca
21
oxygen
fluorine
14.007
± 0.001
15.999
± 0.001
18.998
± 0.001
4
22
Ti
5
23
V
6
24
Cr
7
25
iron
cobalt
58.933
± 0.001
vanadium
chromium
manganese
47.867
± 0.001
50.942
± 0.001
51.996
± 0.001
54.938
± 0.001
rubidium
85.468
± 0.001
55
Cs
41
Nb
42
Mo
43
Tc
44
Ru
Co
45
Rh
10
28
Ni
krypton
83.798
± 0.002
52
53
silver
107.87
± 0.01
palladium
102.91
± 0.01
106.42
± 0.01
56
57-71
barium
132.91
± 0.01
137.33
± 0.01
87
88
Ra
francium
radium
[223]
[226]
lanthanoids
89-103
actinoids
78
79
Pt
Au
48
Cd
49
50
51
cadmium
indium
tin
antimony
tellurium
iodine
xenon
112.41
± 0.01
114.82
± 0.01
118.71
± 0.01
121.76
± 0.01
127.60
± 0.03
126.90
± 0.01
131.29
± 0.01
81
82
Tl
Pb
83
Bi
84
Po
I
54
Sn
80
Te
Kr
In
Hg
Sb
Br
36
79.904
± 0.003
47
Se
35
bromine
Ag
As
34
78.971
± 0.008
46
Ge
33
selenium
Pd
Ga
32
74.922
± 0.001
rhodium
77
31
arsenic
101.07
± 0.02
Ir
39.95
± 0.16
72.630
± 0.008
ruthenium
76
argon
35.45
± 0.01
germanium
[97]
Os
chlorine
32.06
± 0.02
69.723
± 0.001
technetium
75
sulfur
30.974
± 0.001
gallium
95.95
± 0.01
Re
phosphorus
28.085
± 0.001
zinc
molybdenum
74
silicon
26.982
± 0.001
65.38
± 0.02
92.906
± 0.001
W
aluminium
63.546
± 0.003
niobium
73
18
Ar
copper
91.224
± 0.002
Ta
30
17
Cl
nickel
zirconium
72
29
16
S
58.693
± 0.001
88.906
± 0.001
Hf
12
15
P
Zn
yttrium
Ba
11
14
neon
Cu
87.62
± 0.01
strontium
caesium
Fr
40
Zr
27
55.845
± 0.002
titanium
44.956
± 0.001
39
26
9
Fe
scandium
Y
8
Mn
40.078
± 0.004
38
20.180
± 0.001
nitrogen
Si
10
Ne
12.011
± 0.002
calcium
Sr
9
4.0026
± 0.0001
F
carbon
39.098
± 0.001
37
8
O
17
10.81
± 0.02
potassium
Rb
7
N
16
boron
13
Sc
6
C
15
name
Al
3
14
abridged standard
atomic weight
12
22.990
± 0.001
19
5
B
Symbol
Mg
sodium
K
atomic number
4
Be
6.94
± 0.06
13
Key:
85
At
Xe
86
Rn
hafnium
tantalum
tungsten
rhenium
osmium
iridium
platinum
gold
mercury
thallium
lead
bismuth
polonium
astatine
178.49
± 0.01
180.95
± 0.01
183.84
± 0.01
186.21
± 0.01
190.23
± 0.03
192.22
± 0.01
195.08
± 0.02
196.97
± 0.01
200.59
± 0.01
204.38
± 0.01
207.2
± 1.1
208.98
± 0.01
[209]
[210]
[222]
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
Rf
Db
Sg
Bh
Hs
Mt
Ds
Rg
Cn
Nh
Fl
Mc
Lv
Ts
radon
Og
rutherfordium
dubnium
seaborgium
bohrium
hassium
meitnerium
darmstadtium
roentgenium
copernicium
nihonium
flerovium
moscovium
livermorium
tennessine
oganesson
[267]
[268]
[269]
[270]
[269]
[277]
[281]
[282]
[285]
[286]
[290]
[290]
[293]
[294]
[294]
57
La
58
Ce
59
Pr
60
Nd
61
Pm
62
Sm
63
Eu
64
Gd
65
Tb
66
Dy
67
Ho
68
Er
69
Tm
70
Yb
71
Lu
lanthanum
cerium
praseodymium
neodymium
promethium
samarium
europium
gadolinium
terbium
dysprosium
holmium
erbium
thulium
ytterbium
lutetium
138.91
± 0.01
140.12
± 0.01
140.91
± 0.01
144.24
± 0.01
[145]
150.36
± 0.02
151.96
± 0.01
157.25
± 0.03
158.93
± 0.01
162.50
± 0.01
164.93
± 0.01
167.26
± 0.01
168.93
± 0.01
173.05
± 0.02
174.97
± 0.01
89
Ac
90
Th
91
Pa
92
U
93
Np
94
Pu
95
96
97
californium
einsteinium
fermium
mendelevium
nobelium
lawrencium
[251]
[252]
[257]
[258]
[259]
[262]
plutonium
americium
[237]
[244]
[243]
No
103
[247]
neptunium
238.03
± 0.01
Md
102
berkelium
uranium
231.04
± 0.01
Fm
101
[247]
protactinium
232.04
± 0.01
Es
100
curium
thorium
[227]
Cf
99
Cm
actinium
Bk
98
Am
Lr
For notes and updates to this table, see www.iupac.org. This version is dated 4 May 2022.
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