An Overview about the Chemical Element Yttrium


Symbol: Y

Atomic Number: 39

Atomic Mass: 88.90585 amu (atomic mass units)

Melting Point: 1523.0°C (1796.15 K, 2773.4°F)

Boiling Point: 3337.0°C (3610.15 K, 6038.6°F)

Number of Protons: 39

Number of Electrons: 39

Number of Neutrons: 50

Classification: Transition Metal

Crystal Structure: Hexagonal

Density @ 293 K: 4.469 grams per cubic centimeter

Color: Silver

In 1794, Johann Gadolin working in Finland discovered yttria or yttrium oxide in the mineral gadolinite. It is named after the Swedish village of Ytterby which is near Vaxholm. This village is near a quarry which was the source of many minerals, including the gadolinite sample, yielding a number of elements. The elements which have been isolated from minerals found in this quarry include yttrium, erbium, terbium and ytterbium all of which were named after the village.

In 1828, Friedrich Wohler produced an impure sample of the element by the reduction of anhydrous yttrium chloride with potassium. Until modern extraction methods were developed it was extremely difficult to obtain a pure sample of yttrium.

Today yttrium is extracted from minerals that are also the source of many rare earth elements of the lanthanide series such as monazite sand. Initially the elements are extracted as salts using hydrochloric acid, sulfuric acid sodium hydroxide. To obtain pure element from these salts requires a number of techniques including ion exchange chromatography and solvent extraction.

Pure yttrium has a silvery metallic luster. Turnings of the pure element can be ignited in air. There is only one naturally occurring isotope of this element, yttrium-89, which is stable. Nearly 50 man-made isotopes of yttrium have been recognized with half lives that range from about 150 nanoseconds to 58.51 days. Yttrium was one of the elements identified in the moon rocks bought back to earth by the Apollo missions.

Uses for yttrium and its compounds include:

* Adding strength to alloys of which include the metals chromium, aluminum, or magnesium.

* It acts as a catalyst for ethene polymerization

* The phosphor which gives the red color in television screens is made of yttrium oxide and yttrium orthovanadate combined with europium.

* Man-made garnets combining yttrium and iron are used in microwave communication technologies as microwave filters

* Other man-made garnets, produced from aluminum and yttrium, are used in jewelry manufacturing as simulated diamonds.

* Yttrium iron garnets are used in acoustic technology as they are very efficient transmitters and transducers of acoustic energy.

* Yttrium garnets are used in laser technologies.

* Another potential use for yttrium oxide is in the making of glass and ceramics. This compound has a high melting point and can give glass an increased shock resistance as well as lower its expansion characteristics.