Scandium (Sc) – element 21
Scandium is a chemical element with the symbol Sc and atomic number 21. It is a transition metal in group 3, period 4 of the periodic table (d-block), and is a solid at room temperature.
Scandium (Sc) has atomic number 21, atomic mass 44.956 u and electron configuration [Ar] 3d1 4s2.
Scandium facts
| Symbol | Sc |
|---|---|
| Atomic number | 21 |
| Atomic mass | 44.956 u (g/mol) |
| Category | transition metal |
| Group | group 3 |
| Period | 4 |
| Block | d-block |
| Phase at 20 °C | Solid |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s2 3d1 |
| Noble-gas notation | [Ar] 3d1 4s2 |
| Electrons per shell | 2, 8, 9, 2 |
Bohr model and shells
Scandium has 21 electrons in 4 shells: 2, 8, 9, 2. Full configuration and noble-gas notation are in the table; work out any element or ion with the electron configuration calculator.
Physical and atomic properties
| Melting point | 1814 K (1540.8 °C) |
|---|---|
| Boiling point | 3109 K (2835.8 °C) |
| Density | 2.985 g/cm³ |
| Electronegativity (Pauling) | 1.36 |
| Electron affinity | 18 kJ/mol |
| Ionization energies | 633.1, 1235, 2388.6 kJ/mol (1st, 2nd, 3rd) |
| Molar heat capacity | 25.52 J/(mol·K) |
| Discovered by | Lars Fredrik Nilson |
Use the atomic mass in the molar mass calculator for any formula containing Sc.
Position in the periodic table
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Frequently asked questions
What is the atomic mass of scandium?
The atomic mass of scandium is 44.956 u, so one mole of scandium atoms weighs 44.956 g.
What is the electron configuration of scandium?
Scandium has 21 electrons: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹, or [Ar] 3d¹ 4s² in noble-gas notation. Electrons per shell: 2, 8, 9, 2.
Is scandium a metal?
Yes. Scandium is a transition metal.
Where is scandium on the periodic table?
Scandium is in group 3, period 4, in the d-block.
Data: Periodic-Table-JSON (CC BY-SA 3.0); standard atomic weights from IUPAC (abridged). Values in brackets are the mass number of the longest-lived isotope.