Indium (In) - Element 49 | Properties & Electron Configuration
What is Indium?
Indium (In) is element 49, a post transition metal in period 5, group 13. Its electron configuration is 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p¹.
| Atomic Number | 49 |
| Symbol | In |
| Atomic Mass | 114.82 u |
| Category | Post Transition Metal |
| Period | 5 |
| Group | 13 |
| Block | p |
| Electron Configuration | 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p¹ |
| Short Config | [Kr] 4d¹⁰ 5s² 5p¹ |
| Electronegativity | 1.78 |
| Atomic Radius | 167 pm |
| Ionization Energy | 558 kJ/mol |
| Electron Affinity | 29 kJ/mol |
| Phase (STP) | Solid |
Electron Configuration
The full electron configuration of Indium is 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p¹. In noble gas shorthand, this is written as [Kr] 4d¹⁰ 5s² 5p¹.
Indium is a p-block element in group 13, period 5.
Periodic Trends
Electronegativity: Indium has a Pauling electronegativity of 1.78. Within group 13, electronegativity generally decreases down the group.
Atomic Radius: 167 pm. Across period 5, atomic radius generally decreases left to right as nuclear charge increases.
Ionization Energy: 558 kJ/mol. Ionization energy generally increases across a period and decreases down a group.
View all 118 elements with trend overlays for electronegativity, atomic radius, ionization energy, and electron affinity.
Explore Indium on the Interactive Periodic TableRelated Topics
Boron (B)
Properties of Boron - same group as Indium
Aluminum (Al)
Properties of Aluminum - same group as Indium
Gallium (Ga)
Properties of Gallium - same group as Indium
Rubidium (Rb)
Properties of Rubidium - same period as Indium
Strontium (Sr)
Properties of Strontium - same period as Indium
Yttrium (Y)
Properties of Yttrium - same period as Indium