Antimony Facts

Antimony (atomic number 51) 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, the 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, and release 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 and Properties

• 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

Symbol

• Sb

Atomic Weight

• 121.760

References

• _{Los Alamos National Laboratory (2001)}
• _{Crescent Chemical Company (2001)}
• _{Lange's Handbook of Chemistry (1952)}
• _{CRC Handbook of Chemistry & Physics (18th Ed.)}