Antimony

Antimony, ₅₁Sb

Antimony
Pronunciation	UK /ˈæntɪməni/ (AN-tim-ə-nee) US /ˈæntəmoʊni/ (AN-tə-moh-nee)
Appearance	sillery lustrous gray
Standard atomic weight Ar, std(Sb)	7002121760000000000♠121.760(1)
Mass number	Sb:
Antimony in the periodic cairt
Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Airn Cobalt Nickel Capper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Siller (element) Cadmium Indium Tin Antimony Tellurium Iodine Xenon Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gowd Mercur (element) Thallium Leid (element) Bismuth Polonium Astatine Radon Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Ununtrium Flerovium Ununpentium Livermorium Ununseptium Ununoctium As ↑ Sb ↓ Bi tin ← antimony → tellurium
Atomic nummer (Z)	51
Group	group 15 (pnictogens)
Period	period 5
Block	p-block
Element category	Metalloid
Electron confeeguration	[Kr] 4d10 5s2 5p3
Electrons per shell	2, 8, 18, 18, 5
Pheesical properties
Phase at STP	solit
Meltin pynt	903.78 K ​(630.63 °C, ​1167.13 °F)
Bylin pynt	1860 K ​(1587 °C, ​2889 °F)
Density (near r.t.)	6.697 g/cm3
when liquid (at m.p.)	6.53 g/cm3
Heat o fusion	19.79 kJ/mol
Heat o vapourisation	193.43 kJ/mol
Molar heat capacity	25.23 J/(mol·K)
Vapour pressur P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 807 876 1011 1219 1491 1858
Atomic properties
Oxidation states	−3, −2, −1, 0, +1, +2, +3, +4, +5 (an amphoteric oxide)
Electronegativity	Pauling scale: 2.05
Ionisation energies	(more)
Atomic radius	empirical: 140 pm
Covalent radius	139±5 pm
Van der Waals radius	206 pm
Spectral lines o antimony
Ither properties
Naitural occurrence	Sb: Primordial
Creestal structur	​trigonal
Speed o soond thin rod	3420 m/s (at 20 °C)
Thermal expansion	11 µm/(m·K) (at 25 °C)
Thermal conductivity	24.4 W/(m·K)
Electrical resistivity	417 n Ω·m (at 20 °C)
Magnetic orderin	diamagnetic
Young's modulus	55 GPa
Shear modulus	20 GPa
Bulk modulus	42 GPa
Mohs haurdness	3.0
Brinell haurdness	294 MPa
CAS Nummer	7440-36-0
History
Diskivery	3000 BC
First isolation	Vannoccio Biringuccio (1540)
Main isotopes o antimony
Iso­tope Abun­dance Hauf-life (t1/2) Decay mode Pro­duct 121Sb 57.36% - (SF) 123Sb 42.64% - (SF) 125Sb syn 2.7582 y β− 125Te
Decay modes in parentheses are predictit, but hae nae yet been observed

Antimony is a chemical element wi seembol Sb (frae Laitin: stibium) an atomic nummer 51. A lustrous gray metalloid, it is foond in naitur mainly as the sulfide mineral stibnite (Sb₂S₃). Antimony compoonds hae been kent syne auncient times an wur uised for cosmetics; metallic antimony wis an aa kent, but it wis erroneously identified as leid. It wis established tae be an element aroond the 17t century.