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Periodic Table
IUPAC Periodic Table of the Elements
1
2
He
helium
18
4.0026
±0.0001
3
Li
lithium
6.94
±0.06
4
Be
beryllium
2
9.0122
±0.0001
13
14
15
16
9
F
fluorine
17
18.998
±0.001
10
Ne
neon
20.18
±0.001
11
Na
sodium
22.99
±0.001
12
Mg
magnesium
24.305
±0.002
13
Al
aluminium
26.982
±0.001
17
Cl
chlorine
35.45
±0.01
18
Ar
argon
39.95
±0.16
19
K
potassium
39.098
±0.001
20
Ca
calcium
40.078
±0.004
21
Sc
scandium
3
44.956
±0.001
22
Ti
titanium
4
47.867
±0.001
23
V
vanadium
5
50.942
±0.001
24
Cr
chromium
6
51.996
±0.001
25
Mn
manganese
7
54.938
±0.001
26
Fe
iron
8
55.845
±0.002
27
Co
cobalt
9
58.933
±0.001
28
Ni
nickel
10
58.693
±0.001
29
Cu
copper
11
63.546
±0.003
30
Zn
zinc
12
65.38
±0.02
31
Ga
gallium
69.723
±0.001
35
Br
bromine
79.904
±0.003
36
Kr
krypton
83.798
±0.002
37
Rb
rubidium
85.468
±0.001
38
Sr
strontium
87.62
±0.01
39
Y
yttrium
88.906
±0.001
40
Zr
zirconium
91.224
±0.002
41
Nb
niobium
92.906
±0.001
42
Mo
molybdenum
95.95
±0.01
43
Tc
technetium
[97]
44
Ru
ruthenium
101.07
±0.02
45
Rh
rhodium
102.91
±0.01
46
Pd
palladium
106.42
±0.01
47
Ag
silver
107.87
±0.01
48
Cd
cadmium
112.41
±0.01
49
In
indium
114.82
±0.01
50
Sn
tin
118.71
±0.01
53
I
iodine
126.9
±0.01
54
Xe
xenon
131.29
±0.01
55
Cs
caesium
132.91
±0.01
56
Ba
barium
137.33
±0.01
57-71
lanthanoids
72
Hf
hafnium
178.49
±0.01
73
Ta
tantalum
180.95
±0.01
74
W
tungsten
183.84
±0.01
75
Re
rhenium
186.21
±0.01
76
Os
osmium
190.23
±0.03
77
Ir
iridium
192.22
±0.01
78
Pt
platinum
195.08
±0.02
79
Au
gold
196.97
±0.01
80
Hg
mercury
200.59
±0.01
81
Tl
thallium
204.38
±0.01
82
Pb
lead
207.2
±1.1
83
Bi
bismuth
208.98
±0.01
85
At
astatine
[210]
86
Rn
radon
[222]
87
Fr
francium
[223]
88
Ra
radium
[226]
89-103
actinoids
104
Rf
rutherfordium
[267]
105
Db
dubnium
[268]
106
Sg
seaborgium
[269]
107
Bh
bohrium
[270]
108
Hs
hassium
[269]
109
Mt
meitnerium
[277]
110
Ds
darmstadtium
[281]
111
Rg
roentgenium
[282]
112
Cn
copernicium
[285]
113
Nh
nihonium
[286]
114
Fl
flerovium
[290]
115
Mc
moscovium
[290]
116
Lv
livermorium
[293]
117
Ts
tennessine
[294]
118
Og
oganesson
[294]
57
La
lanthanum
138.91
±0.01
58
Ce
cerium
140.12
±0.01
59
Pr
praseodymium
140.91
±0.01
60
Nd
neodymium
144.24
±0.01
61
Pm
promethium
[145]
62
Sm
samarium
150.36
±0.02
63
Eu
europium
151.96
±0.01
64
Gd
gadolinium
157.25
±0.03
65
Tb
terbium
158.93
±0.01
66
Dy
dysprosium
162.5
±0.01
67
Ho
holmium
164.93
±0.01
68
Er
erbium
167.26
±0.01
69
Tm
thulium
168.93
±0.01
70
Yb
ytterbium
173.05
±0.02
71
Lu
lutetium
174.97
±0.01
89
Ac
actinium
[227]
90
Th
thorium
232.04
±0.01
91
Pa
protactinium
231.04
±0.01
92
U
uranium
238.03
±0.01
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
[262]
Key:
atomic number
Symbol
name
abridged standard atomic weight
For notes and updates to this table, see www.iupac.org. This version is dated 4 May 2022.
Copyright © 2022 IUPAC, the International Union of Pure and Applied Chemistry
Copyright © 2022 IUPAC, the International Union of Pure and Applied Chemistry
IUPAC Periodic Table of the Elements
2
He
helium
4.0026
±0.0001
3
Li
lithium
6.94
±0.06
4
Be
beryllium
9.0122
±0.0001
9
F
fluorine
18.998
±0.001
10
Ne
neon
20.18
±0.001
11
Na
sodium
22.99
±0.001
12
Mg
magnesium
24.305
±0.002
13
Al
aluminium
26.982
±0.001
17
Cl
chlorine
35.45
±0.01
18
Ar
argon
39.95
±0.16
19
K
potassium
39.098
±0.001
20
Ca
calcium
40.078
±0.004
21
Sc
scandium
44.956
±0.001
22
Ti
titanium
47.867
±0.001
23
V
vanadium
50.942
±0.001
24
Cr
chromium
51.996
±0.001
25
Mn
manganese
54.938
±0.001
26
Fe
iron
55.845
±0.002
27
Co
cobalt
58.933
±0.001
28
Ni
nickel
58.693
±0.001
29
Cu
copper
63.546
±0.003
30
Zn
zinc
65.38
±0.02
31
Ga
gallium
69.723
±0.001
35
Br
bromine
79.904
±0.003
36
Kr
krypton
83.798
±0.002
37
Rb
rubidium
85.468
±0.001
38
Sr
strontium
87.62
±0.01
39
Y
yttrium
88.906
±0.001
40
Zr
zirconium
91.224
±0.002
41
Nb
niobium
92.906
±0.001
42
Mo
molybdenum
95.95
±0.01
43
Tc
technetium
[97]
44
Ru
ruthenium
101.07
±0.02
45
Rh
rhodium
102.91
±0.01
46
Pd
palladium
106.42
±0.01
47
Ag
silver
107.87
±0.01
48
Cd
cadmium
112.41
±0.01
49
In
indium
114.82
±0.01
50
Sn
tin
118.71
±0.01
53
I
iodine
126.9
±0.01
54
Xe
xenon
131.29
±0.01
55
Cs
caesium
132.91
±0.01
56
Ba
barium
137.33
±0.01
57
La
lanthanum
138.91
±0.01
58
Ce
cerium
140.12
±0.01
59
Pr
praseodymium
140.91
±0.01
60
Nd
neodymium
144.24
±0.01
61
Pm
promethium
[145]
62
Sm
samarium
150.36
±0.02
63
Eu
europium
151.96
±0.01
64
Gd
gadolinium
157.25
±0.03
65
Tb
terbium
158.93
±0.01
66
Dy
dysprosium
162.5
±0.01
67
Ho
holmium
164.93
±0.01
68
Er
erbium
167.26
±0.01
69
Tm
thulium
168.93
±0.01
70
Yb
ytterbium
173.05
±0.02
71
Lu
lutetium
174.97
±0.01
72
Hf
hafnium
178.49
±0.01
73
Ta
tantalum
180.95
±0.01
74
W
tungsten
183.84
±0.01
75
Re
rhenium
186.21
±0.01
76
Os
osmium
190.23
±0.03
77
Ir
iridium
192.22
±0.01
78
Pt
platinum
195.08
±0.02
79
Au
gold
196.97
±0.01
80
Hg
mercury
200.59
±0.01
81
Tl
thallium
204.38
±0.01
82
Pb
lead
207.2
±1.1
83
Bi
bismuth
208.98
±0.01
85
At
astatine
[210]
86
Rn
radon
[222]
87
Fr
francium
[223]
88
Ra
radium
[226]
89
Ac
actinium
[227]
90
Th
thorium
232.04
±0.01
91
Pa
protactinium
231.04
±0.01
92
U
uranium
238.03
±0.01
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
[262]
104
Rf
rutherfordium
[267]
105
Db
dubnium
[268]
106
Sg
seaborgium
[269]
107
Bh
bohrium
[270]
108
Hs
hassium
[269]
109
Mt
meitnerium
[277]
110
Ds
darmstadtium
[281]
111
Rg
roentgenium
[282]
112
Cn
copernicium
[285]
113
Nh
nihonium
[286]
114
Fl
flerovium
[290]
115
Mc
moscovium
[290]
116
Lv
livermorium
[293]
117
Ts
tennessine
[294]
118
Og
oganesson
[294]
For notes and updates to this table, see www.iupac.org. This version is dated 4 May 2022.
Copyright © 2022 IUPAC, the International Union of Pure and Applied Chemistry
Copyright © 2022 IUPAC, the International Union of Pure and Applied Chemistry
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