Discovery date : 1863
Discovered by: Ferdinand Reich and Hieronymous Richter
Origin of the name: The name comes from the Latin 'indicium', meaning violet or indigo.
Allotropes :
~>INDIUM is a chemical element with symbol In and atomic number 49. It is a post-transition metal that makes up 0.21 parts per million of the crust.
| FACT BOX | |||
| Group | 13 | Melting point | 156.60°C, 313.88°F, 429.75 K |
| Period | 5 | Boiling point | 2027°C, 3681°F, 2300 K |
| Block | p | Density (g cm−3) | 7.31 |
| Atomic number | 49 | Relative atomic mass | 114.818 |
| State at 20°C | Solid | Key isotopes | 115 In |
| Electron configuration | [Kr] 4d105s25p1 | CAS number | 7440-74-6 |
| ChemSpider ID | 4514408 | ChemSpider is a free chemical structure database | |
Indium was discovered in 1863 by Ferdinand Reich at the Freiberg School of Mines in Germany. Reich was investigating a sample of the mineral zinc blende (now known as sphalerite, ZnS) which he believed might contain the recently discovered element thallium. From it he obtained a yellow precipitate which he thought was thallium sulfide, but his atomic spectroscope showed lines that were not those of thallium. However, because he was colour-blind he asked Hieronymous Richter to look at the spectrum, and he noted a brilliant violet line, and this eventually gave rise to the name indium, from the Latin word indicum meaning violet.
Working together Reich and Richter isolated a small sample of the new element and announced its discovery. Subsequently the two men fell out when Reich learned that when Richter, on a visit to Paris, claimed he was the discover.