Atomic number | 49 |
Atomic mass | 114.82 g.mol -1 |
Electronegativity | 2 |
Density | 7.31 g.cm-3 at 20°C |
Melting point | 156 °C |
Boiling point | 2000 °C |
Vanderwaals radius | 0.162 nm |
Ionic radius | 0.092 nm (+2) |
Isotopes | 11 |
Electronic shell | [ Kr ] 4d10 5s25p1 |
Energy of first ionisation | 558.2 kJ.mol -1 |
Energy of second ionisation | 1820.2 kJ.mol -1 |
Energy of third ionisation | 2704 kJ.mol -1 |
Standard potential | - 0.34 V ( In3+/ In ) |
Discovered by | Ferdinand Reich 1863 |
Indium is a soft, ductile, manleable, lustrous metallic metal. Its colour is silvery white and it has a face-centered tetragonal structure. It is liquid over a wide range of temperatures, like gallium that belongs to its same group. Both indium and gallium are able to wet glass. Indium is stable in air and in water but dissolves in acids. When heated above its melting point it ignites burning with a violet flame.
Applications
Indium is used in low-melting fusible alloys and as a protective plate for bearings and other metal surfaces. It can be used to form corrosion-resistant mirror surface: when evaporated and allowed to deposit on glass it produces a mirror as good a quality as that of silver. Indium foils are used to assess what is going on inside nuclear reactors. Finally, it is used as light filter in low pressure sodium vapor lamps.