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21Sc

Element 21

Scandium

Transition metals

Scandium (Sc) is in the d-block of the periodic table — group 3, period 4.

Scandium is a chemical element with symbol Sc and atomic number 21.

Key data

Atomic number
21
Atomic mass
44.956 u
Group / Period
3 / 4
Block
d-block
Phase at STP
Solid
Density
2.985 g/cm³
Melting point
1540.8 °C
Boiling point
2835.8 °C
Electron configuration
[Ar] 3d1 4s2

Periodic table block

Scandium is in the d-block (group 3, period 4). Elements land in the d-block when their highest-energy electrons fill a d subshell — these are the transition metals in the middle of the table.

s-blockp-blockd-blockf-block

New to this? Periodic table blocks explained: s, p, d, and f

Common uses

  • Aerospace alloys
  • Stadium lighting
  • Bicycle frames

Discovery

Year: 1879

Discovered by: Lars Fredrik Nilson

Frequently asked questions

What is the atomic number of Scandium?

Scandium has atomic number 21. Its symbol is Sc and its atomic mass is 44.956 u.

What category of element is Scandium?

Scandium is classified as transition metals. It sits in group 3, period 4 of the periodic table.

What block of the periodic table is Scandium in?

Scandium is in the d-block (group 3, period 4). Its highest-energy electrons occupy the d subshell — you can see this in its electron configuration, [Ar] 3d1 4s2.

What is Scandium used for?

Common uses of Scandium include: Aerospace alloys, Stadium lighting, Bicycle frames.

When was Scandium discovered?

Scandium was discovered in 1879 by Lars Fredrik Nilson.

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