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Oxidation & Electrons | Appearance & Characteristics Reactions | Compounds | Radius | Conductivity Abundance & Isotopes
Silver nuggets, found in the field - native silver. |
General:
| Name: Silver | Symbol: Ag |
| Type: Transition Metal | Atomic weight: 107.868 |
| Density @ 293 K: 10.5 g/cm3 | Atomic volume: 10.3 cm3/mol |
| Discovered: Silver has been known since ancient times. Evidence suggests that silver was being separated from lead as early as 3000 B.C. The name silver is derived from the Anglo-Saxon 'seolfor' meaning silver. Its chemical symbol, Ag, is an abbreviation of the Latin word for silver, 'argentum'. | |
States
| State (s, l, g): solid | |
| Melting point: 1235.1 K (961.95 oC) | Boiling point: 2428 K (2155 oC) |
Energies
| Specific heat capacity: 0.235 J g-1 K-1 | Heat of atomization: 284 kJ mol-1 |
| Heat of fusion: 11.30 kJ mol-1 | Heat of vaporization: 250.580 kJ mol-1 |
| 1st ionization energy: 731 kJ mol-1 | 2nd ionization energy: 2073.5 kJ mol-1 |
| 3rd ionization energy: 3360.6 kJ mol-1 | Electron affinity: 125.6 kJ mol-1 |
Oxidation & Electrons
| Shells: 2,8,18,18,1 | Electron configuration: [Kr] 4d10 5s1 |
| Minimum oxidation number: 0 | Maximum oxidation number: 3 |
| Min. common oxidation no.: 0 | Max. common oxidation no.: 1 |
| Electronegativity (Pauling Scale): 1.93 | Polarizability volume: 7.9 Å3 |
Appearance & Characteristics
| Structure: fcc: face-centered cubic | Color: silver |
| Hardness: 2.5 mohs | |
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Harmful effects:
Silver is considered to be non-toxic. However, most silver salts are poisonous and some may be carcinogenic. Characteristics: Silver is a soft, ductile, malleable, lustrous metal. It has the highest electrical and thermal conductivity of all metals. Silver is stable in oxygen and water, but tarnishes when exposed to sulfur compounds in air or water to form a black sulfide layer. Uses: Sterling silver (an alloy of 92.5% silver and 7.5% copper) or Britannia silver (an alloy of 95.8% silver and 4.2% copper) are used for jewelry and silverware. Silver is used as a food additive/coloring and is given the E number E174. About 30% of silver produced is used in the photographic industry, mostly as silver nitrate. Silver is used in solders, electrical contacts, and silver-cadmium and silver-zinc batteries. Silver paints are used in the manufacture of electronic printed circuits. It is used in superior mirror production, as silver is the best known reflector of visible light, although it does tarnish over time. Silver iodide is used in artificial rain making to seed clouds. Silver compounds were used successfully to prevent infection in World War 1. |
Reactions
| Reaction with air: mild, ⇒ Ag2O | Reaction with 6 M HCl: none |
| Reaction with 3 M HNO3: mild, ⇒ AgNO3 | Reaction with 6 M NaOH: |
Compounds
| Oxide(s): Ag2O, AgO (silver peroxide:Ag2O.Ag2O3) | Chloride(s): AgCl |
| Hydride(s): none |
Radius
| Atomic radius: 160 pm | Ionic radius (1+ ion): 128 pm |
| Ionic radius (2+ ion): 108 pm | Ionic radius (3+ ion): 89 pm |
| Ionic radius (2- ion): pm | Ionic radius (1- ion): pm |
Conductivity
| Thermal conductivity: 429 W m-1 K-1 | Electrical conductivity: 63.0 x 106 S m-1 |
Abundance & Isotopes
| Abundance earth's crust: 75 parts per billion by weight, 20 parts per billion by moles | |
| Abundance solar system: 1 part per billion by weight, 10 parts per trillion by moles | |
| Cost, pure: $120 per 100g | |
| Cost, bulk: $14 per 100g | |
| Source: Silver is found in elemental form and also in various ores such as argentite (silver sulfide, Ag2S) and horn silver (silver chloride, AgCl). Commercially, the main sources of silver are copper, copper-nickel, gold, lead, and lead-zinc ores. Silver is extracted from the anode waste sludges of electrolytic copper-refining. | |
| Isotopes: Silver has 35 isotopes whose half-lives are known, with mass numbers 94 to 128. Of these, two are stable, 107Ag and 109Ag. | |