Atomic Number: 51
Atomic Weight: 121.760
Discovery: Antimony compounds have been known since ancient time. The metal has been known since at least the 17th century.
Electron Configuration: [Kr] 5s2 4d10 5p3
Word Origin: Greek anti plus monos, meaning a metal not found alone. The symbol comes from the mineral stibnite.
Properties: The melting point of antimony is 630.74°C, boiling point is 1950°C, specific gravity is 6.691 (at 20°C), with a valence of 0, -3, +3, or +5. Two allotropic forms of antimony exist: the usual stable metallic form and the amorphous gray form. Metallic antimony is extremely brittle. It is a bluish white metal with a flaky crystalline texture and metallic luster. It is not oxidized by air at room temperature. However, it will burn brilliantly when heated, releasing white Sb2O3 fumes. It is a poor heat or electrical conductor. Antimony metal has a hardness of 3 to 3.5.
Uses: Antimony is widely used in alloying to increase hardness and mechanical strength. Antimony is used in the semiconductor industry for infrared detectors, Hall-effect devices, and diodes. The metal and its compounds also used in batteries, bullets, cable sheathing, flame-proofing compounds, glass, ceramics, paints, and pottery. Tartar emetic has been used in medicine. Antimony and many of its compounds are toxic.
Sources: Antimony is found in over 100 minerals. Sometimes it occurs in native form, but it is more common as the sulfide stibnite (Sb2S3) and as the antimonides of heavy metals and as oxides.
Element Classification: Semimetallic
Density (g/cc): 6.691
Melting Point (K): 903.9
Boiling Point (K): 1908
Appearance: hard, silvery-white, brittle semi-metal
Atomic Radius (pm): 159
Atomic Volume (cc/mol): 18.4
Covalent Radius (pm): 140
Ionic Radius: 62 (+6e) 245 (-3)
Specific Heat (@20°C J/g mol): 0.205
Fusion Heat (kJ/mol): 20.08
Evaporation Heat (kJ/mol): 195.2
Debye Temperature (K): 200.00
Pauling Negativity Number: 2.05
First Ionizing Energy (kJ/mol): 833.3
Oxidation States: 5, 3, -2
Lattice Structure: Rhombohedral
Lattice Constant (Å): 4.510
References: Los Alamos National Laboratory (2001), Crescent Chemical Company (2001), Lange's Handbook of Chemistry (1952), CRC Handbook of Chemistry & Physics (18th Ed.)
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