Quick Facts
| Property | Value |
|---|---|
| Symbol | Sc |
| Atomic Number | 21 |
| Atomic Mass | 44.956 u |
| Category | Transition Metal |
| Period | 4 |
| Group | 3 |
| Block | d |
| Electron Configuration | [Ar] 3d¹ 4s² |
Physical Properties
| Property | Value |
|---|---|
| State at 20°C | Solid |
| Density | 2.99 g/cm³ |
| Melting Point | 1541°C (1814 K) |
| Boiling Point | 2836°C (3109 K) |
| Appearance | Silvery-white metal |
Atomic Properties
| Property | Value |
|---|---|
| Electron Configuration | [Ar] 3d¹ 4s² |
| Electronegativity | 1.36 (Pauling scale) |
| First Ionization Energy | 633.1 kJ/mol |
| Atomic Radius | 162 pm |
| Covalent Radius | 170 pm |
| Van der Waals Radius | 211 pm |
History and Discovery
Discovered by: Lars Fredrik Nilson Year of Discovery: 1879 Location: Uppsala, Sweden
Etymology
Scandium is named after "Scandia," the Latin name for Scandinavia, where it was discovered.
Discovery Story
Lars Fredrik Nilson discovered scandium in 1879 while analyzing the rare earth minerals euxenite and gadolinite. He was searching for the element predicted by Dmitri Mendeleev in 1871 as "eka-boron." Per Teodor Cleve identified scandium as eka-boron, confirming Mendeleev's prediction. Metallic scandium was first produced in 1937.
Isotopes
| Isotope | Natural Abundance | Half-life | Decay Mode |
|---|---|---|---|
| ⁴⁵Sc | 100% | Stable | - |
| ⁴⁶Sc | Synthetic | 83.8 days | β⁻ |
Occurrence
Natural Abundance
Scandium is relatively rare, comprising about 22 ppm of Earth's crust. It is widely dispersed and rarely concentrated in mineable deposits. Found in minerals like thortveitite (the only scandium "ore"), wolframite, and as a byproduct of uranium processing.
Extraction and Production
- Byproduct Recovery: From uranium tailings and other mineral processing
- Solvent Extraction: From rare earth concentrates
- Metallothermic Reduction: Of scandium fluoride with calcium
- Global production: about 15-25 tons annually
Applications and Uses
Aerospace Applications
- Scandium-aluminum alloys (extremely strong and lightweight)
- Aircraft components
- Spacecraft structures
- High-performance sports equipment
Lighting
- Metal halide lamps (high-intensity discharge lighting)
- Stadium and studio lighting
- Produces light similar to natural sunlight
Electronics
- Solid oxide fuel cells (electrolyte material)
- Semiconductor research
Sports Equipment
- Baseball bats
- Bicycle frames
- Lacrosse sticks
- Golf clubs
Biological Role
Scandium has no known biological role and is not essential for any organism.
In the Human Body
Scandium is not normally present in the body. Trace amounts may be absorbed from food and water.
Toxicity Studies
Limited data available; scandium compounds are considered low toxicity.
Safety and Hazards
Toxicity
Scandium compounds have relatively low toxicity. However, safety data is limited due to the element's rarity.
Handling Precautions
- Fine powder may be flammable
- Standard laboratory precautions recommended
- Limited exposure data available
- Handle as potentially hazardous
Environmental Impact
Scandium's rarity means environmental impacts are minimal. Mining operations have typical industrial impacts.
Interesting Facts
- Scandium was the first element named after a region (Scandinavia)
- Adding just 0.1-0.5% scandium to aluminum dramatically improves strength and corrosion resistance
- Scandium is more expensive than gold due to its rarity and difficult extraction
- The Soviet MiG-29 fighter jet used scandium-aluminum alloys
- Scandium was predicted by Mendeleev 8 years before its discovery