Yttrium

Source of the photo
http://periodictable.com/Elements/039/index.html
Author of the description
Gruiz Katalin

Atomic number

39

Atomic mass

88.9059 g.mol -1

Electronegativity

1.2

Density

4.47 g.cm-3 at 20°C

Melting point

1500 °C

Boiling point

3336 °C

Vanderwaals radius

0.106 nm (+3)

Isotopes

10

Electronic shell

[ Kr ] 4d1 5s2

Energy of first ionisation

626 kJ.mol -1

Energy of second ionisation

1185 kJ.mol -1

Energy of third ionisation

1980 kJ.mol -1

Discovered by

Johann Gadolin in 1794

 

Yttrium is a highly crystalline iron-gray, rare-earth metal. Yttrium is fairly stable in air, because it is proteced by the formation by the formation of a stable oxide film on its surface, but oxidizes readily when heated. It reacts with water decomposing it to release hydrogen gas, and it reacts with mineral acids. Shavings or turnings of the metal can ignite in air when they exceed 400 °C. When yttrium is finely divided it is very unstable in air.

Applications

The largest use of the element is as its oxide yttria, Y2O3, which is used in making red phosphors for color television picture tubes. Yttrium metal has found some use alloyed in small amounts with other metals and It is used to increase the strength of aluminium and magnesium alloys. When added to cast iron it make the metal more workable. Although metals are generally very good at conducting heat, there is an alloy of yttrium with chromium and aluminium which is heat resistant. Yttrium oxide in glass makes it heat- and shock-resistant, and is used for camera lenses. Yttrium oxide is suitable to making superconductors, which are metal oxides which conduct electricity without any loss of energy.