A Periodic Table of the Elements at Los Alamos National Laboratory
                        Los Alamos National Laboratory's Chemistry Division Presents
                      Periodic Table of the Elements
             A Resource for Elementary, Middle School, and High School Students
                      Click an element for more information:
                         Group**
             Period                  
                           1                                                                                                            18
                           IA                                                                                                         VIIIA
                          1A                                                                                                           8A
                            1       2                                                                    13    14    15 16 17            2
                 1         H IIA                                                                        IIIA IVA VA VIAVIIA He
                          1.008    2A                                                                   3A 4A 5A 6A 7A 4.003
                            3       4                                                                     5     6     7     8     9     10
                 2        Li Be                                                                          B C N O F Ne
                          6.941   9.012                                                                 10.81 12.01 14.01 16.00 19.00 20.18
                           11      12       3      4    5     6      7     8      9     10 11 12 13            14     15   16    17     18
                 3        Na Mg IIIB IVBVB VIBVIIB ------- VIII                              IB IIB Al Si P S Cl Ar
                          22.99   24.31    3B 4B 5B 6B 7B                      -------       1B 2B 26.98 28.09 30.9732.07 35.45 39.95
                                                                          ------- 8 -------
                           19      20       21    22    23    24    25     26     27    28   29    30    31    32     33   34    35     36
                 4         K Ca Sc Ti V CrMn Fe CoNiCuZnGaGeAsSe Br Kr
                          39.10   40.08   44.96 47.8850.94 52.00 54.94 55.85 58.47 58.69 63.55 65.39 69.72 72.59 74.92 78.96 79.90 83.80
                           37      38       39    40    41    42    43     44     45    46   47    48    49    50     51   52    53     54
                 5        Rb Sr Y ZrNbMoTc Ru RhPdAgCd In Sn SbTe I Xe
                          85.47   87.62   88.91 91.2292.91 95.94 (98)     101.1 102.9 106.4 107.9 112.4 114.8 118.7 121.8 127.6 126.9 131.3
                           55      56       57    72    73    74    75     76     77    78   79    80    81    82     83   84    85     86
                 6        Cs Ba La*HfTa W Re Os Ir PtAuHgTl Pb BiPo At Rn
                          132.9   137.3   138.9 178.5180.9 183.9 186.2 190.2 190.2 195.1 197.0 200.5 204.4 207.2 209.0 (210) (210) (222)
                           87      88       89    104 105    106    107   108    109   110   111   112         114         116         118
                 7        Fr Ra Ac~RfDbSg Bh Hs Mt ------ ---                                                 ---         ---          ---
                          (223)   (226)   (227) (257) (260) (263) (262) (265) (266)     ()    ()    ()          ()          ()          ()
                                                                                                           
                                                                                                           
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    A Periodic Table of the Elements at Los Alamos National Laboratory
                                       58    59   60   61    62    63    64    65   66   67   68    69   70   71
                                      Ce PrNdPmSmEu GdTbDyHoErTmYbLu
            Lanthanide Series*
                                      140.1 140.9144.2 (147) 150.4 152.0 157.3 158.9 162.5 164.9 167.3 168.9 173.0 175.0
                                       90    91   92   93    94    95    96    97   98   99   100  101   102  103
             Actinide Series~         Th Pa U Np PuAmCmBkCfEsFmMdNoLr
                                      232.0 (231) (238) (237) (242) (243) (247) (247) (249) (254) (253) (256) (254) (257)
                                       ** Groups are noted by 3 notation conventions.
                    For a list of a the element names and symbols in alphabetical order, click here
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                                                              Table
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   Hydrogen 
                                                       
          Hydrogen
          For rocket fuel
           Atomic Number:            1
           Atomic Symbol:            H
           Atomic Weight:         1.0079
           Electron Configuration:  1s1
  History
  (Gr. hydro, water, and genes, forming) Hydrogen was prepared many years before it was
  recognized as a distinct substance by Cavendish in 1776.
  Named by Lavoisier, hydrogen is the most abundant of all elements in the universe. The heavier
  elements were originally made from Hydrogen or from other elements that were originally
  made from Hydrogen.
  Sources
  Hydrogen is estimated to make up more than 90% of all the atoms or three quarters of the mass
  of the universe. This element is found in the stars, and plays an important part in powering the
  universe through both the proton-proton reaction and carbon-nitrogen cycle -- stellar hydrogen
  fusion processes that release massive amounts of energy by combining Hydrogen to form
  Helium.
  Production of hydrogen in the U.S. alone now amounts to about 3 billion cubic feet per year.
  Hydrogen is prepared by
        steam on heated carbon,
        decomposition of certain hydrocarbons with heat,
        action of sodium or potassium hydroxide on aluminum
        electrolysis of water, or
        displacement from acids by certain metals.
  Liquid hydrogen is important in cryogenics and in the study of superconductivity, as its melting
  point is only 20 degrees above absolute zero.
  Tritium is readily produced in nuclear reactors and is used in the production of the hydrogen
  bomb.
  Hydrogen is the primary component of Jupiter and the other gas giant planets.   At some depth in the
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   Hydrogen 
  planet's interior the pressure is so great that solid molecular hydrogen is converted to solid metallic
  hydrogen.
  In 1973, a group of Russian experimenters may have produced metallic hydrogen at a pressure of 2.8
                                                               3. Earlier, in 1972, at Livermore,
  Mbar. At the transition the density changed from 1.08 to 1.3 g/cm
  California, a group also reported on a similar experiment in which they observed a pressure-volume point
  centered at 2 Mbar. Predictions say that metallic hydrogen may be metastable; others have predicted it
  would be a superconductor at room temperature.
  Compounds
  Although pure Hydrogen is a gas we find very little of it in our atmosphere.   Hydrogen gas is so
  light that uncombined Hydrogen will gain enough velocity from collisions with other gases that
  they will quickly be ejected from the atmosphere.   On earth, hydrogen occurs chiefly in
  combination with oxygen in water, but it is also present in organic matter such as living plants,
  petroleum, coal, etc. It is present as the free element in the atmosphere, but only to the extent of
  less than 1 ppm by volume. The lightest of all gases, hydrogen combines with other elements --
  sometimes explosively -- to form compounds.
  Uses
  Great quantities are required commercially for the fixation of nitrogen from the air in the Haber
  ammonia process and for the hydrogenation of fats and oils. It is also used in large quantities in
  methanol production, in hydrodealkylation, hydrocracking, and hydrodesulfurization. Other
  uses include rocket fuel, welding, producing hydrochloric acid, reducing metallic ores, and
  filling balloons.
  The lifting power of 1 cubic foot of hydrogen gas is about 0.07 lb at 0C, 760 mm pressure.
  The Hydrogen Fuel cell is a developing technology that will allow great amounts of electrical
  power to be obtained using a source of hyrogen gas. 
  Consideration is being given to an entire economy based on solar- and nuclear-generated
  hydrogen. Public acceptance, high capital investment, and the high cost of hydrogen with
  respect to today's fuels are but a few of the problems facing such an economy.   Located in
  remote regions, power plants would electrolyze seawater; the hydrogen produced would travel
  to distant cities by pipelines. Pollution-free hydrogen could replace natural gas, gasoline, etc.,
  and could serve as a reducing agent in metallurgy, chemical processing, refining, etc. It could
  also be used to convert trash into methane and ethylene.
  Forms
  Quite apart from isotopes, it has been shown that under ordinary conditions hydrogen gas is a
  mixture of two kinds of molecules, known as ortho- and para-hydrogen, which differ from one
  another by the spins of their electrons and nuclei.
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