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In support of all the students who are displaced from school due to the Corona virus. Access to physics zone and chemistry zone lessons are now available free of charge. This will be maintained at least through August 1st 2020. Learn and be well.

Chemistry Lessons Review Links

The Alphabetical Elements

Element Symbol Atomic No.
(in AMU)
Atomic Mass
(in AMU)
Actinium Ac
89
227.028
Aluminum Al
13
26.9815
Americium Am
95
(243)
Antimony Sb
51
121.75
Argon Ar
18
39.948
Arsenic As
33
74.9216
Astatine At
85
(210)
Barium Ba
56
137.33
Berkelium Bk
97
(247)
Beryllium Be
4
9.01218
Bismuth Bi
83
208.980
Boron B
5
10.81
Bromine Br
35
79.904
Cadmium Cd
48
112.41
Calcium Ca
20
40.08
Californium Cf
98
(251)
Carbon C
6
12.011
Cerium Ce
58
140.12
Cesium Cs
55
132.905
Chlorine Cl
17
35.453
Chromium Cr
24
51.996
Cobalt Co
27
58.9332
Copper Cu
29
63.546
Curium Cm
96
(247)
Dysprosium Dy
66
162.50
Einsteinium Es
99
(252)
Erbium Er
68
167.26
Europium Eu
63
151.96
Fermium Fm
100
(257)
Fluorine F
9
18.9984
Francium Fr
87
(223)
Gadolinium Gd
64
157.25
Gallium Ga
31
69.72
Germanium Ge
32
72.59
Gold Au
79
196.967
Hafnium Hf
72
178.49
Helium He
2
4.0026
Holmium Ho
67
164.930
Hydrogen H
1
1.0079
Indium In
49
114.82
Iodine I
53
126.905
Iridium Ir
77
192.22
Iron Fe
26
55.847
Krypton Kr
36
83.80
Lanthanum La
57
138.906
Lawrencium Lr
103
(260)
Lead Pb
82
207.2
Lithium Li
3
6.941
Lutetium Lu
71
174.967
Magnesium Mg
12
24.305
Manganese Mn
25
54.9380
Mendelevium Md
101
(258)
Mercury Hg
80
200.59
Molybdenum Mo
42
95.94
Neodymium Nd
60
144.24
Neon Ne
10
20.179
Neptunium Np
93
237.048
Nickel Ni
28
58.69
Niobium Nb
41
92.9064
Nitrogen N
7
14.007
Nobelium No
102
(259)
Osmium Os
76
190.2
Oxygen
O
8
15.9994
Palladium Pd
46
106.42
Phosphorus P
15
30.9738
Platinum Pt
78
195.08
Plutonium Pu
94
(244)
Polonium Po
84
(210)
Potassium K
19
39.0983
Praseodymium Pr
59
140.908
Promethium Pm
61
(145)
Protactinium Pa
91
231.036
Radium Ra
88
226.025
Radon Rn
86
(222)
Rhenium Re
75
186.207
Rhodium Rh
45
102.906
Rubidium Rb
37
85.4678
Ruthenium Ru
44
101.07
Samarium Sm
62
150.36
Scandium Sc
21
44.9559
Selenium Se
34
78.96
Silicon Si
14
28.0855
Silver Ag
47
107.868
Sodium Na
11
22.9898
Strontium Sr
38
87.62
Sulfur S
16
32.06
Tantalum Ta
73
180.948
Technetium Tc
43
(98)
Tellurium Te
52
127.60
Terbium Tb
65
158.925
Thallium Tl
81
204.383
Thorium Th
90
232.038
Thulium Tm
69
168.934
Tin Sn
50
118.71
Titanium Ti
22
47.88
Tungsten W
74
183.85
Unnilpentium Unp
105
(262)
Unnilhexium Unh
106
(263)
Unnilquadium Unq
104
(261)
Uranium U
92
238.029
Vanadium V
23
50.9415
Xenon Xe
54
131.29
Ytterbium Yb
70
173.04
Yttrium Y
39
88.9059
Zinc Zn
30
65.39
Zirconium Zr
40
91.224

     Masses in (parentheses) indicate the mass for the most abundant or stable isotope.