Relative Atomic Masses of the Chemical Elements

James Richard Fromm


Name            Symbol  Atomic Number  Atomic Mass
Actinium          Ac         89         227.0278
Aluminum(a)       Al         13          26.98154
Americium         Am         95        (243)
Antimony          Sb         51         121.75*
Argon(b,c)        Ar         18          39.948*
Arsenic           As         33          74.9216
Astatine          At         85        (210)
Barium(c)         Ba         56         137.33
Berkelium         Bk         97        (247)
Beryllium         Be          4           9.01218
Bismuth           Bi         83         208.9804
Boron(b,d)        B           5          10.81
Bromine           Br         35          79.904
Cadmium(c)        Cd         48         112.41
Cesium            Cs         55         132.9054
Calcium(c)        Ca         20          40.08
Californium       Cf         98        (251)
Carbon(b)         C           6          12.011
Cerium(c)         Ce         58         140.12
Chlorine          Cl         17          35.453
Chromium          Cr         24          51.996
Cobalt            Co         27          58.9332
Copper(b)         Cu         29          63.546*
Curium            Cm         96        (247)
Dysprosium        Dy         66         162.50*
Einsteinium       Es         99        (254)
Erbium            Er         68         167.26*
Europium(c)       Eu         63         151.96
Fermium           Fm        100        (257)
Fluorine          F           9          18.998403
Francium          Fr         87        (223)
Gadolinium(c)     Gd         64         157.25*
Gallium           Ga         31          69.72
Germanium         Ge         32          72.59*
Gold              Au         79         196.9665
Hafnium           Hf         72         178.49*
Helium(c)         He          2           4.00260
Holmium           Ho         67         164.9304
Hydrogen(b)       H           1           1.0079
Indium(b)         In         49         114.82
Iodine            I          53         126.9045
Iridium           Ir         77         192.22*
Iron              Fe         26          55.847*
Krypton(c,d)      Kr         36          83.80
Lanthanum(c)      La         57         138.9055*
Lawrencium        Lr        103        (260)
Lead(b,c)         Pb         82         207.2
Lithium(b,c,d)    Li          3           6.941*
Lutetium          Lu         71         174.97
Magnesium(c)      Mg         12          24.305
Manganese         Mn         25          54.9380
Mendelevium       Md        101        (258)
Mercury           Hg         80         200.59*
Molybdenum        Mo         42          95.94
Neodymium(c)      Nd         60         144.24*
Neon(d)           Ne         10          20.179*
Neptunium(a)      Np         93         237.0482
Nickel            Ni         28          58.70
Niobium           Nb         41          92.9064
Nitrogen          N           7          14.0067
Nobelium          No        102        (259)
Osmium(c)         Os         76         190.2
Oxygen(b)         O           8          15.9994*
Palladium(b)      Pd         46         106.4
Phosphorus        P          15          30.97376
Platinum          Pt         78         195.09*
Plutonium         Pu         94        (244)
Polonium          Po         84        (209)
Potassium         K          19          39.0983*
Praseodymium      Pr         59         140.9077
Promethium        Pm         61        (145)
Protactinium(a)   Pa         91         231.0359
Radium(a,c)       Ra         88         226.0254
Radon             Rn         86        (222)
Rhenium           Re         75         186.207
Rhodium           Rh         45         102.9055
Rubidium(c)       Rb         37          85.4678*
Ruthenium(c)      Ru         44         101.07*
Samarium(c)       Sm         62         150.4
Scandium          Sc         21          44.9559
Selenium          Se         34          78.96*
Silicon           Si         14          28.0855*
Silver(c)         Ag         47         107.868
Sodium            Na         11          22.98977
Strontium(c)      Sr         38          87.62
Sulfur(b)         S          16          32.06
Tantalum          Ta         73         180.9479*
Technetium        Tc         43         (97)
Tellurium(c,d)    Te         52         127.60*
Terbium           Tb         65         158.9254
Thallium          Tl         81         204.37*
Thorium(a,c)      Th         90         232.0381
Thulium           Tm         69         168.9342
Tin               Sn         50         118.69*
Titanium          Ti         22          47.90*
Tungsten          W          74         183.85*
Uranium(c,d)      U          92         238.029
Vanadium          V          23          50.9414*
Xenon(c,d)        Xe         54         131.30
Ytterbium         Yb         70         173.04*
Yttrium           Y          39          88.9059
Zinc              Zn         30          65.38
Zirconium(c)      Zr         40          91.22

Main Tables

Auxiliary Tables


Copyright 1997 James R. Fromm