| Group | 13 | Melting point | 156.6 oC, 313.88 oF, 429.75 K |
| Period | 5 | Boiling point | 2072 oC, 3761.6 oF, 2345.15 K |
| Block | p | Density (kg m-3) | 7290 |
| Atomic number | 49 | Relative atomic mass | 114.818 |
| State at room temperature | Solid | Key isotopes | 115In |
| Electron configuration | [Kr] 4d105s25p1 | CAS number | 7440-74-6 |
| ChemSpider ID | 4514408 | ChemSpider is a free chemical structure database | |
Image explanation
The symbol used here is the Japanese kanji character “hon”, meaning origin, and reflects the naming of the element after its indigo blue spectrum line. The Japanese discovered that cotton was a difficult fabric to dye except with indigo. Consequently, organic indigo dye was widely used throughout the Edo period (1603 - 1867) as a colouring and designing agent for cotton textiles.
Appearance
A soft, silvery metal that is stable and used in low-melting alloys for fire-sprinkler systems in shops and warehouses. Some semi-conductors and transistors are made of indium arsenide or indium antimonide.
Uses
Indium has semiconductor uses in transistors, thermistors and photoconductors. It is also used to make low-temperature alloys; for example, an alloy of 24% indium-76% gallium is liquid at room temperature. Indium can also be plated on to metal and evaporated on to glass to give a mirror with better resistance to corrosion than silver. A tiny long-lived indium battery has been devised to power new electronic watches.
Biological role
Indium has no known biological role but has been shown to cause birth defects in unborn children.
Natural abundance
Indium is often associated with zinc minerals and iron, lead and copper ores. It is commercially produced from the zinc minerals, usually as a by-product.
| Atomic radius, non-bonded (Å) | 1.930 | Covalent radius (Å) | 1.42 |
| Electron affinity (kJ mol-1) | 28.935 |
Electronegativity (Pauling scale) |
1.780 |
|
Ionisation energies (kJ mol-1) |
1st
558.298
2nd
1820.706
3rd
2704.482
4th
5210.204
5th
-
6th
-
7th
-
8th
-
|
||
|
|
| Common oxidation states | 3 | ||||
| Isotopes | Isotope | Atomic mass | Natural abundance (%) | Half life | Mode of decay |
| 115In | 114.904 | 95.71 | 4.4 x 1014 y | β- | |
|
Molar heat capacity (J mol-1 K-1) |
26.74 | Young's modulus (GPa) | Unknown | |||||||||||
| Shear modulus (GPa) | Unknown | Bulk modulus (GPa) | Unknown | |||||||||||
| Vapour pressure | ||||||||||||||
| Temperature (K) |
|
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| Pressure (Pa) |
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Videos of the elements. Additional videos will be coming in 2012.
Images: Visual Elements © Murray Robertson 2011
Mining and Sourcing data: British Geological Survey – natural environment research council.
Text: John Emsley Nature’s Building Blocks: An A-Z Guide to the Elements, Oxford University Press, 2nd Edition, 2011.
Data: CRC Handbook of Chemistry and Physics, CRC Press, 92nd Edition, 2011.
G. W. C. Kaye and T. H. Laby Tables of Physical and Chemical Constants, Longman, 16th Edition, 1995.
Members of the RSC can access these books through our library.
Mining and Sourcing data: British Geological Survey – natural environment research council.
Text: John Emsley Nature’s Building Blocks: An A-Z Guide to the Elements, Oxford University Press, 2nd Edition, 2011.
Data: CRC Handbook of Chemistry and Physics, CRC Press, 92nd Edition, 2011.
G. W. C. Kaye and T. H. Laby Tables of Physical and Chemical Constants, Longman, 16th Edition, 1995.
Members of the RSC can access these books through our library.
