49In114.818
Indium
Post-Transition Metal
Solid at STP
Period 5Group 13Block PDiscovered 1863
[Kr]5s2 4d10 5p1
Indium is a chemical element with symbol In and atomic number 49. It is a post-transition metallic element that is rare in Earth's crust. The metal is very soft, malleable and easily fusible, with a melting point higher than sodium, but lower than lithium or tin.
📖 Read more on Wikipedia →Atomic Properties
| Atomic Number | 49 |
| Atomic Mass | 114.818 u |
| Electron Configuration | [Kr]5s2 4d10 5p1 |
| Oxidation States | +3 |
| Electronegativity | 1.78 (Pauling) |
| Atomic Radius | 193 pm |
| Ionization Energy | 5.786 eV |
| Electron Affinity | 0.3 eV |
| Block | P |
Physical Properties
| Appearance | silvery lustrous gray |
| Standard State | Solid |
| Melting Point | 429.75 K (156.6 °C) |
| Boiling Point | 2345 K (2071.8 °C) |
| Density | 7.31 g/cm³ |
| Molar Heat | 26.74 J/(mol·K) |
| CPK Color | #A67573 |
Classification
| Category | Post-Transition Metal |
| Group Block | Post-transition metal |
| Period | 5 |
| Group | 13 |
| Block | P |
Discovery
| Year Discovered | 1863 |
| Discovered By | Ferdinand Reich |
| Electron Shells | 2, 8, 18, 18, 3 |