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31.11: The Chemical Elements (Appendix K)
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Table K1: The Chemical Elements
|
Element
|
Symbol
|
Atomic Number
|
Atomic Weight
1
|
Percentage of Naturally Occurring Elements in the Universe
|
|
Hydrogen
|
H
|
1
|
1.008
|
75
|
|
Helium
|
He
|
2
|
4.003
|
23
|
|
Lithium
|
Li
|
3
|
6.94
|
6 × 10
−7
|
|
Beryllium
|
Be
|
4
|
9.012
|
1 × 10
−7
|
|
Boron
|
B
|
5
|
10.821
|
1 × 10
−7
|
|
Carbon
|
C
|
6
|
12.011
|
0.5
|
|
Nitrogen
|
N
|
7
|
14.007
|
0.1
|
|
Oxygen
|
O
|
8
|
15.999
|
1
|
|
Fluorine
|
F
|
9
|
18.998
|
4 × 10
−5
|
|
Neon
|
Ne
|
10
|
20.180
|
0.13
|
|
Sodium
|
Na
|
11
|
22.990
|
0.002
|
|
Magnesium
|
Mg
|
12
|
24.305
|
0.06
|
|
Aluminum
|
Al
|
13
|
26.982
|
0.005
|
|
Silicon
|
Si
|
14
|
28.085
|
0.07
|
|
Phosphorus
|
P
|
15
|
30.974
|
7 × 10
−4
|
|
Sulfur
|
S
|
16
|
32.06
|
0.05
|
|
Chlorine
|
Cl
|
17
|
35.45
|
1 × 10
−4
|
|
Argon
|
Ar
|
18
|
39.948
|
0.02
|
|
Potassium
|
K
|
19
|
39.098
|
3 × 10
−4
|
|
Calcium
|
Ca
|
20
|
40.078
|
0.007
|
|
Scandium
|
Sc
|
21
|
44.956
|
3 × 10
−6
|
|
Titanium
|
Ti
|
22
|
47.867
|
3 × 10
−4
|
|
Vanadium
|
V
|
23
|
50.942
|
3 × 10
−4
|
|
Chromium
|
Cr
|
24
|
51.996
|
0.0015
|
|
Manganese
|
Mn
|
25
|
54.938
|
8 × 10
−4
|
|
Iron
|
Fe
|
26
|
55.845
|
0.11
|
|
Cobalt
|
Co
|
27
|
58.933
|
3 × 10
−4
|
|
Nickel
|
Ni
|
28
|
58.693
|
0.006
|
|
Copper
|
Cu
|
29
|
63.546
|
6 × 10
−6
|
|
Zinc
|
Zn
|
30
|
65.38
|
3 × 10
−5
|
|
Gallium
|
Ga
|
31
|
69.723
|
1 × 10
−6
|
|
Germanium
|
Ge
|
32
|
72.630
|
2 × 10
−5
|
|
Arsenic
|
As
|
33
|
74.922
|
8 × 10
−7
|
|
Selenium
|
Se
|
34
|
78.971
|
3 × 10
−6
|
|
Bromine
|
Br
|
35
|
79.904
|
7 × 10
−7
|
|
Krypton
|
Kr
|
36
|
83.798
|
4 × 10
−6
|
|
Rubidium
|
Rb
|
37
|
85.468
|
1 × 10
−6
|
|
’Strontium
|
Sr
|
38
|
87.62
|
4 × 10
−6
|
|
Yttrium
|
Y
|
39
|
88.906
|
7 × 10
−7
|
|
Zirconium
|
Zr
|
40
|
91.224
|
5 × 10
−6
|
|
Niobium
|
Nb
|
41
|
92.906
|
2 × 10
−7
|
|
Molybdenum
|
Mo
|
42
|
95.95
|
5 × 10
−7
|
|
Technetium
|
Tc
|
43
|
(98)
|
—
|
|
Ruthenium
|
Ru
|
44
|
101.07
|
4 × 10
−7
|
|
Rhodium
|
Rh
|
45
|
102.906
|
6 × 10
−8
|
|
Palladium
|
Pd
|
46
|
106.42
|
2 × 10
−7
|
|
Silver
|
Ag
|
47
|
107.868
|
6 × 10
−8
|
|
Cadmium
|
Cd
|
48
|
112.414
|
2 × 10
−7
|
|
Indium
|
In
|
49
|
114.818
|
3 × 10
−8
|
|
Tin
|
Sn
|
50
|
118.710
|
4 × 10
−7
|
|
Antimony
|
Sb
|
51
|
121.760
|
4 × 10
−8
|
|
Tellurium
|
Te
|
52
|
127.60
|
9 × 10
−7
|
|
Iodine
|
I
|
53
|
126.904
|
1 × 10
−7
|
|
Xenon
|
Xe
|
54
|
131.293
|
1 × 10
−6
|
|
Cesium
|
Cs
|
55
|
132.905
|
8 × 10
−8
|
|
Barium
|
Ba
|
56
|
137.327
|
1 × 10
−6
|
|
Lanthanum
|
La
|
57
|
138.905
|
2 × 10
−7
|
|
Cerium
|
Ce
|
58
|
140.116
|
1 × 10
−6
|
|
Praseodymium
|
Pr
|
59
|
140.907
|
2 × 10
−7
|
|
Neodymium
|
Nd
|
60
|
144.242
|
1 × 10
−6
|
|
Promethium
|
Pm
|
61
|
(145)
|
—
|
|
Samarium
|
Sm
|
62
|
150.36
|
5 × 10
−7
|
|
Europium
|
Eu
|
63
|
151.964
|
5 × 10
−8
|
|
Gadolinium
|
Gd
|
64
|
157.25
|
2 × 10
−7
|
|
Terbium
|
Tb
|
65
|
158.925
|
5 × 10
−8
|
|
Dysprosium
|
Dy
|
66
|
162.500
|
2 × 10
−7
|
|
Holmium
|
Ho
|
67
|
164.930
|
5 × 10
−8
|
|
Erbium
|
Er
|
68
|
167.259
|
2 × 10
−7
|
|
Thulium
|
Tm
|
69
|
168.934
|
1 × 10
−8
|
|
Ytterbium
|
Yb
|
70
|
173.054
|
2 × 10
−7
|
|
Lutetium
|
Lu
|
71
|
174.967
|
1 × 10
−8
|
|
Hafnium
|
Hf
|
72
|
178.49
|
7 × 10
−8
|
|
Tantalum
|
Ta
|
73
|
180.948
|
8 × 10
−9
|
|
Tungsten
|
W
|
74
|
183.84
|
5 × 10
−8
|
|
Rhenium
|
Re
|
75
|
186.207
|
2 × 10
−8
|
|
Osmium
|
Os
|
76
|
190.23
|
3 × 10
−7
|
|
Iridium
|
Ir
|
77
|
192.217
|
2 × 10
−7
|
|
Platinum
|
Pt
|
78
|
195.084
|
5 × 10
−7
|
|
Gold
|
Au
|
79
|
196.967
|
6 × 10
−8
|
|
Mercury
|
Hg
|
80
|
200.592
|
1 × 10
−7
|
|
Thallium
|
TI
|
81
|
204.38
|
5 × 10
−8
|
|
Lead
|
Pb
|
82
|
207.2
|
1 × 10
−6
|
|
Bismuth
|
Bi
|
83
|
208.980
|
7 × 10
−8
|
|
Polonium
|
Po
|
84
|
(209)
|
—
|
|
Astatine
|
At
|
85
|
(210)
|
—
|
|
Radon
|
Rn
|
86
|
(222)
|
—
|
|
Francium
|
Fr
|
87
|
(223)
|
—
|
|
Radium
|
Ra
|
88
|
(226)
|
—
|
|
Actinium
|
Ac
|
89
|
(227)
|
—
|
|
Thorium
|
Th
|
90
|
232.038
|
4 × 10
−8
|
|
Protactinium
|
Pa
|
91
|
231.036
|
—
|
|
Uranium
|
U
|
92
|
238.029
|
2 × 10
−8
|
|
Neptunium
|
Np
|
93
|
(237)
|
—
|
|
Plutonium
|
Pu
|
94
|
(244)
|
—
|
|
Americium
|
Am
|
95
|
(243)
|
—
|
|
Curium
|
Cm
|
96
|
(247)
|
—
|
|
Berkelium
|
Bk
|
97
|
(247)
|
—
|
|
Californium
|
Cf
|
98
|
(251)
|
—
|
|
Einsteinium
|
Es
|
99
|
(252)
|
—
|
|
Fermium
|
Fm
|
100
|
(257)
|
—
|
|
Mendelevium
|
Md
|
101
|
(258)
|
—
|
|
Nobelium
|
No
|
102
|
(259)
|
—
|
|
Lawrencium
|
Lr
|
103
|
(262)
|
—
|
|
Rutherfordium
|
Rf
|
104
|
(267)
|
—
|
|
Dubnium
|
Db
|
105
|
(268)
|
—
|
|
Seaborgium
|
Sg
|
106
|
(271)
|
—
|
|
Bohrium
|
Bh
|
107
|
(272)
|
—
|
|
Hassium
|
Hs
|
108
|
(270)
|
—
|
|
Meitnerium
|
Mt
|
109
|
(276)
|
—
|
|
Darmstadtium
|
Ds
|
110
|
(281)
|
—
|
|
Roentgenium
|
Rg
|
111
|
(280)
|
—
|
|
Copernicium
|
Cn
|
112
|
(285)
|
—
|
|
Nihonium
|
Nh
|
113
|
(284)
|
—
|
|
Flerovium
|
Fl
|
114
|
(289)
|
—
|
|
Moskovium
|
Mc
|
115
|
(288)
|
—
|
|
Livermorium
|
Lv
|
116
|
(293)
|
—
|
|
Tennessine
|
Ts
|
117
|
(294)
|
—
|
|
Oganesson
|
Og
|
118
|
(294)
|
—
|
Footnotes
-
1
Where mean atomic weights have not been well determined, the atomic mass numbers of the most stable isotopes are given in parentheses.