Quick answerIndium (In) is a post-transition metal with atomic number 49 and an atomic mass of 114.82 (2023), in group 13, period 5. It was discovered by Ferdinand Reich and Hieronymus Theodor Richter in 1863. It is used for touchscreens and LCD displays. Its electron configuration is [Kr] 4d10 5s2 5p1.
Indium is the soft metal behind every touchscreen, its oxide conducts electricity while staying perfectly transparent.
Key facts
| Symbol | In |
|---|---|
| Atomic number | 49 |
| Atomic mass | 114.82 (IUPAC standard atomic weight, 2023) |
| Category | post-transition metal |
| Group | 13 |
| Period | 5 |
| Block | p-block |
| Electron configuration | [Kr] 4d10 5s2 5p1 |
| Discovered | Ferdinand Reich and Hieronymus Theodor Richter, 1863 |
| Uses | touchscreens, LCD displays, solar panels, solder, semiconductors |
Quick quiz
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Keep exploring
- Periodic table — all 118 elements
- Aluminium (Al) — another post-transition metal, atomic number 13
- Gallium (Ga) — another post-transition metal, atomic number 31
- Tin (Sn) — another post-transition metal, atomic number 50
- Thallium (Tl) — another post-transition metal, atomic number 81
- Lead (Pb) — another post-transition metal, atomic number 82
- Bismuth (Bi) — another post-transition metal, atomic number 83
- Polonium (Po) — another post-transition metal, atomic number 84
- Nihonium (Nh) — another post-transition metal, atomic number 113
- Flerovium (Fl) — another post-transition metal, atomic number 114
- Moscovium (Mc) — another post-transition metal, atomic number 115
- All post-transition metal elements — on the periodic table
Sources & last updated
- CIAAW — Standard Atomic Weights
- PubChem Periodic Table
- Wikipedia — Timeline of chemical element discoveries
Last updated: . Figures are shown with their year; where sources disagree, the value is left out rather than estimated.