Silver and it

Silver and its applications:


Silver is a metallic chemical element with the chemical symbol Ag atomic number 47. A soft, white, lustrous transition metal. The metal occurs naturally in its pure, free 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 by-product of copper, gold, lead, and zinc refining.  


Crystal Structure: Face-centered cubic at 25 oC, a = 0.408621 nm

Mass Characteristics:

Atomic Weight: 107.868

Density: 10.49 g/cm3 at 20 oC

Volume Change on Freezing: 5% contraction 

Thermal Properties:

Melting Point: 961.9 oC

Boiling Point: 2163 oC

Coefficient of Linear Thermal Expansion: 20 oC, 19.0 μm/m * K

                                                          -190 to 0 oC, 17.0 μm/m * K 0 to 900 oC,
                                                            Lt = Lo (1 + 19.494 x 10-6 t + 1.0379 x 10-6
                                                            t2 + 2.375 x 10-12t3, where t is inoC
                                                            0 to 100oC, 19.68
μm/m * K

                                                            0 to 500 oC, 20.61 μm/m * K


Specific HeatSolid:  25 oC, 0.235 kJ/kg * K

                                   127 oC, 0.239 kJ/kg * K

                                    527 oC, 0.262 * K

                                    961 oC, 0.297 kJ/kg * K

                        Liquid: 961 to 2227 oC, 0.310 kJ/kg * K

Latent Heat of Fusion: 104.2 kJ/kg

Latent Heat of Vaporization: 2.63 MJ/kg 

Recrystallization Temperature: 20 to 200 oC, depending on purity and amount of cold work

Thermal Conductivity:428 W/m * K at 20 oC

                                    356 W/m * K at 450 oC

Electrical Properties:

Electrical Conductivity: 108.4% IACS for extremely pure silver

Electrical Resistivity: 14.7 nΩ * m at 0 oC

Temperature Coefficient: from 0 to 100 oC, 0.0041 per K

Cold working of silver considerably increases resistivity: 5% for 90% reduction. Annealing commercially pure silver successively in air and hydrogen disrupts grain boundaries and increases resistance. Tension reduces resistivity slightly as does hydrostatic pressure: 12,000 kg/cm2 causes 4% reduction.

Thermal Electromotive Force: vs platinum, +0.74 mV; cold junction at 0 oC, hot junction at 100 oC

 Magnetic Properties:

Magnetic Susceptibility: Volume: -2.27 x 10-6 mks

Optical Properties:

Color: As a result of the high and fairly uniform reflectance in the visible range, silver is considered white, but if human eyes were sensitive to a slightly shorter wavelength region, silver would appear to have color.

Reflectance: For clean silver, high in the visible an infrared but low in near-ultraviolet.

Emittance: Solid silver at 0.65 μm: extremely low and not known accurately; values of 0.044 μm at 940 oC and 0.072 μm at 980 oC have been observed for liquid silver. Other experiments showed no discontinuity at the melting point of silver, the emissivity being about 0.055 at about 700 oC.

Mechanical Properties:

Tensile Properties: Considerable spread in values for tensile strength and hardness of high-purity silver. Average tensile strength, 125 MPa for 5 mm wire annealed at 600 oC.

Hardness: High-purity silver; hydrogen anneal 650 oC, 25 HV; air anneal at 650 oC, 27 HV; electro-deposited silver (higher electrical resistivity than wrought silver), 100 HV

Elastic Modulus: Strained 5%, then heated 0.5 hour at 350 oC, 71.0 GPa

Poisson's Ratio: Annealed: 0.37; hard drawn, 0.39

Liquid Surface Tension: 0.923 N/m at 995 oC  


Silver has long been valued as a precious metal, and it is used to make ornaments, jewellery, high-value tableware, utensils (hence the term silverware), and currency coins. Today, silver metal is also used in electrical contacts and conductors, in mirrors and in catalysis of chemical reactions. Its compounds are used in photographic film and dilute silver nitrate solutions and other silver compounds are used as disinfectants and microbiocides.



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