Silver

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This article is about the chemical element. For the use of silver as a medication, see Medical uses of silver. For other uses, see Silver (disambiguation).

Silver, 47Ag

Silver
Appearance	lustrous white metal
Standard atomic weight Ar, std(Ag)	107.8682(2)[1]
Silver in the periodic table
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 Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium     Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver 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 Gold Mercury (element) Thallium Lead 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 Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson Cu ↑ Ag ↓ Au palladium ← silver → cadmium
Atomic number (Z)	47
Group	group 11
Period	period 5
Block	d-block
Electron configuration	[Kr] 4d10 5s1
Electrons per shell	2, 8, 18, 18, 1
Physical properties
Phase at STP	solid
Melting point	1234.93 K ​(961.78 °C, ​1763.2 °F)
Boiling point	2435 K ​(2162 °C, ​3924 °F)
Density (near r.t.)	10.49 g/cm3
when liquid (at m.p.)	9.320 g/cm3
Heat of fusion	11.28 kJ/mol
Heat of vaporisation	254 kJ/mol
Molar heat capacity	25.350 J/(mol·K)
Vapour pressure P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 1283 1413 1575 1782 2055 2433
Atomic properties
Oxidation states	−2, −1, +1, +2, +3 (an amphoteric oxide)
Electronegativity	Pauling scale: 1.93
Ionisation energies	1st: 731.0 kJ/mol 2nd: 2070 kJ/mol 3rd: 3361 kJ/mol
Atomic radius	empirical: 144 pm
Covalent radius	145±5 pm
Van der Waals radius	172 pm
Spectral lines of silver
Other properties
Natural occurrence	primordial
Crystal structure	​face-centred cubic (fcc)
Speed of sound thin rod	2680 m/s (at r.t.)
Thermal expansion	18.9 µm/(m⋅K) (at 25 °C)
Thermal conductivity	429 W/(m⋅K)
Thermal diffusivity	174 mm2/s (at 300 K)
Electrical resistivity	15.87 nΩ⋅m (at 20 °C)
Magnetic ordering	diamagnetic[2]
Molar magnetic susceptibility	−19.5×10−6 cm3/mol (296 K)[3]
Young's modulus	83 GPa
Shear modulus	30 GPa
Bulk modulus	100 GPa
Poisson ratio	0.37
Mohs hardness	2.5
Vickers hardness	251 MPa
Brinell hardness	206–250 MPa
CAS Number	7440-22-4
History
Discovery	before 5000 BC
Main isotopes of silver
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct 105Ag syn 41.2 d ε 105Pd γ – 106mAg syn 8.28 d ε 106Pd γ – 107Ag 51.839% stable 108mAg syn 418 y ε 108Pd IT 108Ag γ – 109Ag 48.161% stable 110mAg syn 249.95 d β− 110Cd γ – 111Ag syn 7.45 d β− 111Cd γ –
Category: Silver view talk edit  | references

Silver is a chemical element with the symbol Ag (from the Latin argentum, derived from the Proto-Indo-European h₂erǵ: "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal.[citation needed] The metal is found in the Earth's crust in the pure, free elemental form ("native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a byproduct of copper, gold, lead, and zinc refining.

Silver has long been valued as a precious metal. Silver metal is used in many bullion coins, sometimes alongside gold:[4] while it is more abundant than gold, it is much less abundant as a native metal.[5] Its purity is typically measured on a per-mille basis; a 94%-pure alloy is described as "0.940 fine". As one of the seven metals of antiquity, silver has had an enduring role in most human cultures.

Other than in currency and as an investment medium (coins and bullion), silver is used in solar panels, water filtration, jewellery, ornaments, high-value tableware and utensils (hence the term "silverware"), in electrical contacts and conductors, in specialized mirrors, window coatings, in catalysis of chemical reactions, as a colorant in stained glass and in specialised confectionery. Its compounds are used in photographic and X-ray film. Dilute solutions of silver nitrate and other silver compounds are used as disinfectants and microbiocides (oligodynamic effect), added to bandages and wound-dressings, catheters, and other medical instruments.

Contents

• 1Characteristics
  • 1.1Isotopes
• 2Chemistry
• 3Compounds
  • 3.1Oxides and chalcogenides
  • 3.2Halides
  • 3.3Other inorganic compounds
  • 3.4Coordination compounds
  • 3.5Organometallic
  • 3.6Intermetallic
• 4Etymology
• 5History
• 6Symbolic role
• 7Occurrence and production
  • 7.1In marine environments
• 8Monetary use
  • 8.1Price
• 9Applications
  • 9.1Jewellery and silverware
  • 9.2Medicine
  • 9.3Electronics
  • 9.4Brazing alloys
  • 9.5Chemical equipment
  • 9.6Catalysis
  • 9.7Photography
  • 9.8Nanoparticles
  • 9.9Miscellanea
• 10Precautions
• 11See also
• 12References
• 13Sources used above
• 14Further reading