Yttrium was discovered in 1789. Its chemical properties are similar to the elements in the lanthanides series of the periodic table. It is widely used in cathode ray tube display in television, mobiles and laptops.
History and Discovery
In the late 18th century, yttrium was used for various purposes. In 1787, Carl Axel Arrhenius found rock that contain yttrium in Swedish village, named Ytterby. He named that element ytterbite and sent many samples to chemists for analysis. In 1789, Johan Gadolin identified new oxide in Arrhenius sample and published his analysis in 1794 . Ander Gustaf Ekeberg in 1797 confirmed identification and named the new element oxide yttria. In 1828 Friedrich Wohler isolated the metal by reacting yttrium chloride with potassium. Carl Gustaf Mosander in 1843, investigated this metal in depth and found three more oxides, white yttrium oxide, yellow terbium oxide and rose-colored erbium oxide .
|Periodic Table Classification||Group 3
|State at 20C||Solid|
|Electron Configuration||[Kr] 4d1 5s2|
|Electron Shell||2, 8, 18, 9, 2|
|Density||4.47 g.cm-3 at 20°C|
|Atomic Mass||88.91 g.mol -1|
|Electronegativity according to Pauling||1.22|
Yttrium is rare earth mineral found in uranium ores. It is not present in free form. It is considered as the 28th most abundant element in the earth’s crust. It is present in rare earth ores, such as laterite clays, gadolinite (silicate especially iron, beryllium, yttrium, cerium and erbium), euxenite and xenotime (yttrium orthophosphate) are most important. It is also present in edible plants about 20ppm and 100ppm, cabbage contain high amount of yttrium. About 700ppm in the seeds of woody plants. Minami Torishima Island also called as Marcus Island have high amount of rare earth elements and yttrium.
Yttrium is a soft, silver transition metal. It is less electronegative than its predecessor (scandium) and more electronegative than its successor (zirconium) in its group. Yttrium chemical symbol is Y, atomic number is 39 and its atomic weight is 88.9 g/mol. It has high melting point, about 1526oC and boiling point is 2903oC. Its density at room temperature is 4.472g/cm3.
Yttrium is chemically similar to lanthanides. In pure form and in bulk quantity it is highly stable in air due to the formation of protective oxide film. In finely divided form, however, it is highly unstable in air. It can ignite in the air at temperature higher than 400oC. At 1000oC, when it is heated with nitrogen it forms yttrium nitride. It is trivalent metal so it forms inorganic compounds in the oxidation state of +3. It also forms water insoluble fluoride, hydroxide and oxalate. But its bromide, chloride iodide are all soluble in water. Yttrium readily react with water and forms Y2O3. With halogens it forms trihalides like yttrium (III) fluoride (YF3). Similarly yttrium form binary compounds with carbon, silicon, selenium, phosphorous and sulfur. Strong acids can attack yttrium rapidly but concentrated nitric acid and hydrofluoric acid do not .
Significance and Uses
- Yttrium is used in LEDs and phosphorus especially red phosphorous in television set CRT (Cathode ray tube) display.
- It is also used in the production of electronic filters, superconductors, electrolytes and laser.
- Its compounds are used as a catalyst for ethylene polymerization.
- Yttrium used on the electrodes of high-performance spark plugs.
- Yttrium aluminum garnet is used as gemstone in jewelry.
- It is used to increase the strength of aluminum and magnesium alloys.
- Yttrium is used to deoxidize non- ferrous metals.
- Due to its high melting point its oxides are used in ceramics and glass to impart shock resistance.
- Yitrrium-90 is used in drugs for the treatment of various cancer like lymphoma, leukemia, liver and bone cancer.
- Yttrium and iron are used as microwave filters in various microwave communications equipment.
- It is widely used in cell phones and larger display screens.
Some compounds of yttrium can be highly toxic to animals and humans. Its water soluble compounds are mild toxic while insoluble compounds are non -toxic. Continuous and long-term exposure to yttrium may cause lung diseases. As an occupational hazard, workers may experience mild eye, skin and upper respiratory tract irritation.
Isotopes of Yttrium
The most important isotopes of yttrium are 91Y and 90Y having half-lives of 58.51 days and 64 hours. Y-89 is the stable isotope of yttrium and it is present naturally. Yttrium have thirty-two synthetic isotopes which have atomic masses ranging from 76 to 108. The least stable is 106Y with a half -life of ˃105 ns.
. Greenwood 1997, p. 944
. Daane, A. H. (1968). “Yttrium”. In Hampel, Clifford A. The Encyclopedia of the Chemical Elements. New York: Reinhold Book Corporation. pp. 810–821.