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Element 15 - Phosphorus (P) sound

From phosphoros, or light bearer; discovered 1669; occurs in three major forms--white, red, and, rarely, black. The white, so unstable that it yellows, then reddens in light. glows in the dark--hence "phosphorescence." Phosphates are ingredients of detergents.

Properties

Atomic Number: 15
Atomic Weight: 30.97376
Electron Configuration (at ground state): 1s22s22p63s23p3
Oxidation States (Bold most stable): -3, +3, +4, +5
Boiling Point (K): 553
Melting Point (K): 317.3
Density (at 300K -- g/cm3): 1.82
Atomic Volume (at 300K -- cm3/mol) 17.0
Number of stable isotopes: 1
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 32 -- 14.26 days -- beta particle (electron) emission
Covalent Radius (Å): 1.06
Atomic Radius (Å): 1.28
First Ionization Potential (V): 10.486
Electronegativity (Pauling's): 2.19
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.769
Heat of Vaporization (kJ/mol): 12.4
Heat of Fusion (kJ/mol): 0.63
Electrical Conductivity (at 293K for polycrystalline material -- 106 (ohms)-1 cm-1): 10-16
Thermal Conductivity (at 300K -- W m-1 K-1): 0.235
Crystal Structure: Monoclinic
Acid-Base Properties: Slightly acidic