Scandium (Sc) - Element 21 | Properties & Electron Configuration
What is Scandium?
Scandium (Sc) is element 21, a transition metal in period 4, group 3. Its electron configuration is 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹ 4s².
| Atomic Number | 21 |
| Symbol | Sc |
| Atomic Mass | 44.956 u |
| Category | Transition Metal |
| Period | 4 |
| Group | 3 |
| Block | d |
| Electron Configuration | 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹ 4s² |
| Short Config | [Ar] 3d¹ 4s² |
| Electronegativity | 1.36 |
| Atomic Radius | 160 pm |
| Ionization Energy | 633 kJ/mol |
| Electron Affinity | 18 kJ/mol |
| Phase (STP) | Solid |
Electron Configuration
The full electron configuration of Scandium is 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹ 4s². In noble gas shorthand, this is written as [Ar] 3d¹ 4s².
Scandium is a d-block element in group 3, period 4.
Periodic Trends
Electronegativity: Scandium has a Pauling electronegativity of 1.36. Within group 3, electronegativity generally decreases down the group.
Atomic Radius: 160 pm. Across period 4, atomic radius generally decreases left to right as nuclear charge increases.
Ionization Energy: 633 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 Scandium on the Interactive Periodic Table