Jan 8 2004
Background
The chemical formula for Silver Chloride is AgCl. It is usually available as a white crystalline solid. However, due to its light sensitivity it can turn a deep grey blue upon prolonged exposure to light. This is due to its decomposition to silver metal and chlorine.
Silver chloride is virtually insoluble in water, but can be dissolved in aqueous solutions of ammonia, potassium cyanide and sodium thiocyanate.
Applications
Silver chloride is used in:
• Photography films and plates
• Reference electrodes e.g. in pH meters
• Infrared windows where it can be used in contact with many aqueous solutions e.g. in FTIR spectrometers, in which case it can be an alternative to KBr, which is attacked by water.
Key Properties
| Property |
Value |
| Density ( g.cm-3 ) |
5.59 |
| Melting Point ( °C ) |
455 |
| Young’s Modulus (GPa) |
20 |
| Poissons Ratio |
0.4 |
| Co-Efficient of Thermal Expansion ( /°C) at 20 °C |
31x10-6 |
| Dielectric Constant |
12.3 at 1 MHz |
| Refractive Index |
1.98 at 10 µm
2.02 at 1 µm |
| Maximum Recommended Service Temperature (°C) |
200 |
Source: AZoM.com.