Scandium (Sc)
Element 21 · Transition metal · Solid at 25 °C · Group 3, Period 4
Scandium is a scarce, lightweight metal; small additions of it strengthen aluminium alloys used in aerospace parts and high-end sports equipment.
On the periodic table, scandium sits in group 3 in period 4. It is one of 38 elements classified as a transition metal, and at room temperature (25 °C) it is a solid.
Transition metals occupy the wide d-block in the middle of the table. As a family they are hard, dense, high-melting metals that conduct heat and electricity well. Their partly filled d-orbitals let many of them take several oxidation states, form vividly colored compounds, and act as catalysts — which is why so much of industry, and so much of biology, runs on this block.
Properties of scandium
| Atomic number (Z) | 21 |
|---|---|
| Symbol | Sc |
| Atomic mass | 44.956 |
| Category | Transition metal |
| Group | 3 |
| Period | 4 |
| Block | d-block |
| Metal / nonmetal | Metal |
| State at 25 °C | Solid |
| Electron configuration | [Ar] 3d1 4s2 |
| Electronegativity (Pauling) | 1.36 |
| Melting point | 1,541 °C (1,814.15 K / 2,805.8 °F) |
| Boiling point | 2,836 °C (3,109.15 K / 5,136.8 °F) |
| Density | 2.985 g/cm³ |
Position in the periodic table
Scandium shares group 3 with Yttrium (Y). Elements in the same group have the same number of outer electrons, so they tend to behave alike chemically — comparing them is one of the fastest ways to see periodic trends in action.
Physical properties
Scandium melts at 1,541 °C (1,814.15 K / 2,805.8 °F) and boils at 2,836 °C (3,109.15 K / 5,136.8 °F), giving it a liquid range of about 1,295 °C at standard pressure.
Its density is 2.985 g/cm³.
See also: the interactive periodic table, how to read the periodic table, periodic trends.