Periodic table › Silver
1. Identity and classification
Lustrous, brilliant white-metallic solid; possesses the highest electrical conductivity, thermal conductivity, and optical reflectivity of any metal
- Name and symbol
- Silver (Silver) · Ag
- Atomic number
- 47
- Relative atomic weight / mass number
- 107.87 ± 0.01
- Group · period · block
- 11 · 5 · d
- Category
- Transition Metal
- State near room temperature
- Solid
- Stable isotopes
- At least one stable isotope
- CAS number
- 7440-22-4
Square brackets [A] indicate a representative isotope mass number, not an average atomic weight. Neutron counts differ between isotopes.
2. Atomic structure and electron configuration
- Protons · electrons in a neutral atom
- 47 · 47
- Neutrons in reference isotope
- 60 (107Ag)
- Full electron configuration
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s¹- Abbreviated configuration
[Kr]5s¹ 4d¹⁰- Electrons per shell
- 2, 8, 18, 18, 1
- Listed oxidation states
- +1
- Electronegativity
- 1.93 (Pauling)
- First ionization energy
- 730.973 kJ/mol · 7.576 eV
- Electron affinity
- 125.624 kJ/mol
- Covalent radius
- 145 pm
- van der Waals radius
- 172 pm
Configurations of superheavy elements may include theoretical predictions. Different definitions of atomic radius are not interchangeable.
3. Physical and thermal properties
- Density
- 10.501 g/cm³
- Melting point
- 1234.93 K · 961.78 °C · 1763.204 °F
- Boiling point
- 2435 K · 2161.85 °C · 3923.33 °F
- Crystal structure
- FCC
- Specific heat
- 0.235 J/(g·K)
- Thermal conductivity
- 429 W/(m·K)
- Enthalpy of fusion
- 11.28 kJ/mol
- Enthalpy of vaporization
- 250.58 kJ/mol
- Magnetic ordering
- Diamagnetic
- Mohs hardness
- 2.5
- Speed of sound
- 2680 m/s
Density and structure depend on temperature, pressure and allotrope. 25°C is a room-temperature reference, not STP. Unestablished values are not zero.
4. Chemical behavior and compounds
Nitric acid dissolves silver; tarnish commonly contains silver sulfide.
Selected compounds: AgNO₃ (Silver nitrate) · AgBr (Silver bromide) · AgCl (Silver chloride) · Ag₂O (Silver oxide)
Reaction reference
Silver is relatively resistant to air oxidation; sulfur compounds can tarnish it.
No ordinary reaction with water.
5. Isotopes
| Isotope | Status | Natural abundance | Half-life |
|---|---|---|---|
| 107Ag | Stable | 51.839% | Stable |
| 109Ag | Stable | 48.161% | Stable |
Half-life units: s seconds, m minutes, h hours, d days, Y years. A dash means no natural-abundance value is given, not zero. Listed records are selected ground states; metastable states are distinct.
6. Discovery and occurrence
- Discovery
- Known since antiquity; no exact discovery year
- Scientists associated with discovery
- Known since antiquity
- Location
- Ancient Anatolia & Greece
- Origin
- Natural
- Listed crustal abundance
- 0.075 ppm
Minerals and naming reference
Argentite/Acanthite (Ag₂S), Pyrargyrite, Tetrahedrite, Native Silver, and as a byproduct of Cu/Pb/Zn refining
From Anglo-Saxon 'seolfor'; symbol Ag from Latin 'argentum' and Proto-Indo-European '*h₂erǵ-' (shining/white)
7. Applications
Sterling silver jewelry, silverware, high-clarity mirrors, bullion coins, antimicrobial textiles
Detailed applications by field
- everyday
- Sterling silver jewelry, silverware, high-clarity mirrors, bullion coins, antimicrobial textiles
- industry
- Ethylene oxide oxidation catalysts, brazing and soldering alloys, photographic film halides
- electronics
- Conductive silver pastes in membrane switches, RFID antennas, multi-layer ceramic capacitors, and high-reliability contacts
- medicine
- Silver sulfadiazine burn creams, antimicrobial wound dressings, silver-coated catheters
- energy
- Conductive front-side metallization grid lines on crystalline silicon solar photovoltaic cells; silver-oxide batteries
- aerospace
- High-reliability silver-zinc batteries and low-friction bearing coatings in spacecraft
- agriculture
- Silver iodide (AgI) cloud seeding nuclei for precipitation enhancement and hail suppression
- science
- Ag/AgCl reference electrodes in electrochemistry; Surface-Enhanced Raman Spectroscopy (SERS) substrates
8. Biological role and safety
Hazard depends on the isotope, chemical form, dose and exposure route.
Elemental substances, ions, compounds and radioisotopes can have different health effects. This is an educational reference; laboratory work requires the material safety data sheet and trained supervision.
Biological role reference
No known biological role in humans; exhibits strong broad-spectrum oligodynamic antimicrobial activity against bacteria, fungi, and viruses. Chronic overexposure causes argyria (bluish-grey skin discoloration).