49In114.82
Indium (In)
Element 49 · Post-transition metal
Indium (In) is a chemical element with atomic number 49. It is classified as a post-transition metal in period 5, group 13 of the periodic table (the p-block). Its standard atomic weight is 114.82 u and its ground-state electron configuration is [Kr] 4d¹⁰ 5s² 5p¹.
Indium facts
| Atomic number (Z) | 49 |
|---|---|
| Symbol | In |
| Standard atomic weight | 114.82 u |
| Category | Post-transition metal |
| Group | 13 |
| Period | 5 |
| Block | p-block |
| Electron configuration | [Kr] 4d¹⁰ 5s² 5p¹ |
| Electronegativity (Pauling) | 1.78 |
| State at 20 °C | Solid |
| Protons / electrons | 49 / 49 |
| Neutrons (most common isotope, approx.) | 66 |
| Molar mass | 114.82 g/mol |