21Sc44.956
Scandium (Sc)
Element 21 Ā· Transition metal
Scandium (Sc) is a chemical element with atomic number 21. It is classified as a transition metal in period 4, group 3 of the periodic table (the d-block). Its standard atomic weight is 44.956 u and its ground-state electron configuration is [Ar] 3dĀ¹ 4sĀ².
Scandium facts
| Atomic number (Z) | 21 |
|---|---|
| Symbol | Sc |
| Standard atomic weight | 44.956 u |
| Category | Transition metal |
| Group | 3 |
| Period | 4 |
| Block | d-block |
| Electron configuration | [Ar] 3dĀ¹ 4sĀ² |
| Electronegativity (Pauling) | 1.36 |
| State at 20 Ā°C | Solid |
| Protons / electrons | 21 / 21 |
| Neutrons (most common isotope, approx.) | 24 |
| Molar mass | 44.956 g/mol |