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Lanthanum is a silvery white metallic element that belongs to group 3 of the periodic table and is the first element of the lanthanide series.
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Lanthanum and is
Lanthanum () is a chemical element with the symbol La and atomic number 57.
Lanthanum is a malleable, ductile, and soft metal that oxidizes rapidly when exposed to air.
Lanthanum is a soft, malleable, silvery white metal which has hexagonal crystal structure at room temperature.
Lanthanum easily is oxidized ( a centimeter-sized sample will completely oxidize within a year ) and is therefore used as in elemental form only for research purposes.
Lanthanum is quite electropositive and reacts slowly with cold water and quite quickly with hot water to form lanthanum hydroxide:
Lanthanum is the most strongly basic of all the trivalent lanthanides, and this property is what allowed Mosander to isolate and purify the salts of this element.
Lanthanum is relatively easy to purify, since it has only one adjacent lanthanide, cerium, which itself is very readily removed due to its potential tetravalency.
Lanthanum is available in relatively large quantities ( 32 ppm in Earth ’ s crust ).
Lanthanum is taken into consideration as a rare earth metal because the process to mine is difficult, time consuming and expensive.
Lanthanum is most commonly obtained from monazite and bastnäsite.
Lanthanum is separated as a double salt with ammonium nitrate by crystallization.
Lanthanum metal is obtained from its oxide by heating it with ammonium chloride or fluoride and hydrofluoric acid at 300-400 ° C to produce the chloride or fluoride:
* Lanthanum fluoride ( LaF < sub > 3 </ sub >) is an essential component of a heavy fluoride glass named ZBLAN.
* Lanthanum ( III ) oxide ( La < sub > 2 </ sub > O < sub > 3 </ sub >) improves the alkali resistance of glass, and is used in making special optical glasses, such as infrared-absorbing glass, as well as camera and telescope lenses, because of the high refractive index and low dispersion of rare-earth glasses.
Lanthanum oxide is also used as a grain growth additive during the liquid phase sintering of silicon nitride and zirconium diboride.
* Lanthanum oxide additive to tungsten is used in gas tungsten arc welding electrodes, as a substitute for radioactive thorium.
* Lanthanum fluoride is used in phosphor lamp coatings.
The Lanthanum cation La < sup > 3 +</ sup > is a positive allosteric modulator at native and recombinant GABA receptors, increasing open channel time and decreasing desensitization in a subunit configuration dependent manner.
However, when Lanthanum carbonate is used for treating hyperphosphatemia, its side effects, namely myalgia, muscular cramping, and peripheral edema, should be clinically aware of.
Lanthanum and element
* Lanthanum, chemical element with symbol La
Lanthanum and 3
Lanthanum carbonate ( La < sub > 2 </ sub >( CO < sub > 3 </ sub >)< sub > 3 </ sub >) was approved as a medication against renal failure.
Lanthanum exhibits two oxidation states, + 3 and + 2, the former being much more stable.
Lanthanum dissolves readily in dilute sulfuric acid to form solutions containing the La ( III ) ions, which exist as < sup > 3 +</ sup > complexes:
Lanthanum gallium silicate ( referred to as LGS in this article ), also known as langasite, has a chemical formula of the form A < sub > 3 </ sub > BC < sub > 3 </ sub > D < sub > 2 </ sub > O < sub > 14 </ sub >, where A, B, C and D indicate particular cation sites.
Lanthanum and first
* The atomic number of Lanthanum ( La ), the first of the Lanthanides
Lanthanum and .
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, and others.
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 was discovered in 1839 by Swedish chemist Carl Gustav Mosander, when he partially decomposed a sample of cerium nitrate by heating and treating the resulting salt with dilute nitric acid.
Lanthanum was isolated in relatively pure form in 1923.
Lanthanum can also be separated from a solution of rare earth nitrates by liquid-liquid extraction with a suitable organic liquid, such as tributyl phosphalate.
* Lanthanum oxide and the boride are used in electronic vacuum tubes as hot cathode materials with strong emissivity of electrons.
* Lanthanum carbonate was approved as a medication ( Fosrenol, Shire Pharmaceuticals ) to absorb excess phosphate in cases of end-stage renal failure.
is and silvery
Antimony is a silvery, lustrous gray metal that has a Mohs scale hardness of 3.
Americium is a relatively soft radioactive metal with silvery appearance.
It is the fifth element in Group 2, a soft silvery metallic alkaline earth metal.
It is a silvery metallic element that must be extracted by electrolysis from a fused salt like calcium chloride.
Curium is a hard, dense, silvery metal with a relatively high melting point and boiling point for an actinide.
Californium is a silvery white actinide metal with a melting point of 900 ± 30 ° C and an estimated boiling point of 1745 ° C.
A CD or compact disc is a thin plastic silvery disc for audio recordings.
It is a moderately hard, silvery metal which readily oxidizes in air and water.
Einsteinium is a soft, silvery, paramagnetic metal.
Whereas most other pure metals are gray or silvery white, gold is yellow.
A soft silvery metallic poor metal, elemental gallium is a brittle solid at low temperatures.
A lustrous, silvery gray, tetravalent transition metal, hafnium chemically resembles zirconium and is found in zirconium minerals.
Hafnium is a shiny, silvery, ductile metal that is corrosion-resistant and chemically similar to zirconium ( due to its having the same number of valence electrons and being in the same group ).
Lead is a bright and silvery metal with a very slight shade of blue in a dry atmosphere.
The free element, which is a silvery metal with a gray cast, has the sixth-highest melting point of any element.
This holds equally for all photons of the visible spectrum, which is why metals are often silvery white or grayish with the characteristic specular reflection of metallic luster.
It is a soft silvery metal that tarnishes in air.
Freshly cut potassium is silvery in appearance, but it begins to tarnish toward gray immediately after being exposed to air.
Pure radium is a white, silvery, solid metal, melting at 700 ° C ( 1292 ° F ) and boiling at 1737 ° C ( 3159 ° F ), similar to barium.
Scandium is a soft metal with a silvery appearance.
Strontium is a grey, silvery metal that is softer than calcium and even more reactive in water, with which it reacts on contact to produce strontium hydroxide and hydrogen gas.
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