Science / Periodic Table of Elements / Yttrium (Y): 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. Yttrium in the environment: Yttrium never occurs in nature as a free element. It is found in almost all rare earth minerals and in uranium ores. The yellow-brown ore xenotime can contain as much as 50% yttrium phophate (YPO4) and is mined in Malaysia. Yttrium is found in the rare-earth mineral monazite, of which it makes 2.5%, and in smaller quantities in other minerals such as barnasite, fergusonite and smarskite. The output of yttrium is about 600 tonnes per year, measured as yttrium oxide, and world reserves are estimated to be around 9 million tonnes.
Science / Periodic Table of Elements / Yttrium (Y): 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: MORE