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Element 1 - Hydrogen (H) sound

From hydor and gen, or water-forming; discovered 1766 by Henry Cavendish; the lightest element Hydrogen is almost never found free on earth, but the sun and other stars are almost pure hydrogen. The thermonuclear fusion of hydrogen nuclei therefore lights and heats the universe.

Properties

Atomic Number: 1
Atomic Weight: 1.00794
Electron Configuration (at ground state): 1s1
Oxidation States (Bold most stable): +1, -1
Boiling Point (K): 20.28
Melting Point (K): 13.81
Density (at STP -- g/l): 0.0899
Atomic Volume (liquid state at boiling point -- cm3/mol) 14.10
Number of stable isotopes: 2
Number of natural radioactive isotopes: 1
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 3 -- 12.26 years -- beta particle (electron) emission
Covalent Radius (Å): 0.32
Atomic Radius (Å): 2.08
First Ionization Potential (V): 13.598
Electronegativity (Pauling's): 2.10
Specific Heat Capacity (at 300K -- J g-1 K-1): 14.304
Heat of Vaporization (kJ/mol): 0.4581
Heat of Fusion (kJ/mol): 0.0585
Thermal Conductivity (at 300K -- W m-1 K-1): 0.1815
Crystal Structure: Hexagonal
Acid-Base Properties (for representative oxides): Amphoteric