Yttrium (Y)

Four elements are named after the same Swedish village: yttrium, ytterbium, terbium and erbium all come from Ytterby, a quarry outside Stockholm, and gadolinium, holmium, thulium and scandium were first found in its ore too. Yttrium barium copper oxide, discovered in 1987, was the first superconductor to work above 77 K, which meant liquid nitrogen instead of liquid helium and turned superconductivity from an exotic laboratory condition into something a workshop could sustain. A trace of yttrium was found in the lunar rocks brought back by Apollo 11.

Properties

Atomic number

39

Symbol

Y

Standard atomic weight

88.906 u

Category

Transition metal

Group

3

Period

5

Block

d-block

Electron configuration

[Kr] 5s² 4d¹

Electrons per shell

2, 8, 18, 9, 2

Melting point

1,795 K — 1521.8 °C — 2771.3 °F

Boiling point

3,618 K — 3344.8 °C — 6052.7 °F

Density

4.47 g/cm³

Electronegativity

1.22 (Pauling)

Oxidation states

+3

Discovered

1794 by Johan Gadolin

Electron configuration

Full

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹

Noble gas shorthand

[Kr] 5s² 4d¹

Shells

K: 2 · L: 8 · M: 18 · N: 9 · O: 2

What it is used for

• YAG laser crystals for cutting, marking and eye surgery
• Yttria-stabilised zirconia in thermal barrier coatings and dental crowns
• Red phosphors in older colour television tubes and fluorescent lamps
• The Y in YBCO, the first superconductor to work above liquid nitrogen
• Yttrium-90 microspheres for treating liver tumours

Neighbours in the table

Group 3

Elements in the same group share their outer electron count, which is why they behave similarly in reactions. Yttrium sits in group 3 with scandium.