Carl Gustaf Mosander was a Swedish chemist born on September 10, 1797 — died on October 15, 1858. Mosander work revealed existence of numerous lanthanum, erbium, terbium and didymium rare-earth elements.
What are rare earth elements?
Rare earth elements is one of a set of seventeen chemical elements in the periodic table, specifically the fifteen lanthanides, as well as scandium and yttrium.
The rare earth elements are all metals, and the group is often referred to as the “rare earth metals.” These metals have many similar properties and that often causes them to be found together in geologic deposits. They are also referred to as “rare earth oxides” because many of them are typically sold as oxide compounds.
Rare earth metals and alloys that contain them are used in many devices that people use every day such as computer memory, DVDs, rechargeable batteries, cell phones, catalytic converters, magnets, fluorescent lighting and much more. Even many rechargeable batteries are made with rare earth compounds.
Rare earths are used as catalysts, phosphors, and polishing compounds. These are used for air pollution control, illuminated screens on electronic devices, and the polishing of optical-quality glass.
Rare earth elements play an essential role in our national defense. The military uses night-vision goggles, precision-guided weapons, communications equipment, GPS equipment, batteries and other defense electronics.
Lanthanum Metal Element
Lanthanum white rare-earth metal element and it is the first element of the lanthanide series. Lanthanum compounds have numerous applications as catalysts, additives in glass, carbon lighting for studio lighting and projection, ignition elements in lighters and torches, electron cathodes, scintillators.
Lanthanum exhibits two oxidation states, +3 and +2. Lanthanum metal reacts with all the halogens. Lanthanum combines with nitrogen, carbon, sulfur, phosphorus, boron, selenium, silicon and arsenic at elevated temperatures, forming binary compounds.
Lanthanum is most commonly obtained from monazite and bastnasite. Lanthanum is separated as a double salt with ammonium nitrate by crystallization. Lanthanum can also be separated from a solution of rare earth nitrates by liquid-liquid extraction with a suitable organic liquid, such as tributyl phosphate.
Erbium Chemical Element
Erbium silvery-white solid metal and it is associated with several other rare elements in the mineral gadolinite from Ytterby. It is commonly used as a photographic filter, and because of its resilience it is useful as a metallurgical additive.
Terbium Rare Earth Element
Terbium is malleable, ductile and very hard silvery-white rare earth metal. Terbium is used to dope calcium fluoride, calcium tungstate and strontium molybdate, materials that are used in solid-state devices and as a crystal stabilizer of fuel cells which operate at elevated temperatures.