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Lanthanum continues the trend started by two lighter members in general chemical behavior, while lutetium behaves more similarly to yttrium.
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Lanthanum and by
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 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 phosphalate.
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 was discovered in 1839 by Mosander, when he partially decomposed a sample of cerium nitrate by heating and treating the resulting salt with dilute nitric acid.
Lanthanum and two
Lanthanum exhibits two oxidation states, + 3 and + 2, the former being much more stable.
Lanthanum and chemical
Lanthanum () is a chemical element with the symbol La and atomic number 57.
* Lanthanum, chemical element with symbol La
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 .
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.
Lanthanum is a malleable, ductile, and soft metal that oxidizes rapidly when exposed to air.
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 carbonate ( La < sub > 2 </ sub >( CO < sub > 3 </ sub >)< sub > 3 </ sub >) was approved as a medication against renal failure.
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 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 isolated in relatively pure form in 1923.
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 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 oxide and the boride are used in electronic vacuum tubes as hot cathode materials with strong emissivity of electrons.
* 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 carbonate was approved as a medication ( Fosrenol, Shire Pharmaceuticals ) to absorb excess phosphate in cases of end-stage renal failure.
* Lanthanum fluoride is used in phosphor lamp coatings.
continues and trend
Many ancient cultures used adorned daggers in ritual and ceremonial purposes, a trend which continues to the present time in the form of art knives.
* as a result, and the trend continues to this day.
If the trend continues, more than half the forest that existed when Papua New Guinea became independent from Australia in 1975 will be gone by 2021.
This trend continues in later R-Type games-some Bits have the ability to use a miniature version of the Red weapon of some Forces.
It is assumed this trend continues as Starfleet adopts a more traditional military role and assumes its regular place as the exploratory and defensive arm of the United Federation of Planets.
* In response to NASA research confirming 2010 tied for the warmest year on record, James Hanson, Chief Climate Scientist and Director, Goddard Institute for Space Studies at NASA, stated: " if the warming trend continues, as is expected, if greenhouse gases continue to increase, the 2010 record will not stand for long.
As this trend continues, he believes he is shrinking and sees his physician, Dr. Bramson ( William Schallert ) who reassures him that he is in perfect health and that " people just don't get shorter.
* Apple introduces the iMac computer, initiating a trend in computer design towards translucent plastics and multicolor case design, discontinuing many legacy technologies like serial ports, and beginning a resurgence in the company's fortunes that continues unabated to this day.
Branch membership has been on a steep incline overall and continues to trend upwards, as does shop organizing.
A world peace may thus become possible if this trend continues and if the democratic peace theory is correct.
Most telephone companies now also function as internet service providers ( ISPs ), and the distinction between a telephone company and an ISP may disappear completely over time, as the current trend for supplier convergence in the industry continues.
Contrary to the fashion industry's celebrity trend of the previous decade, lingerie retailer Victoria's Secret continues to groom and launch young talents into supermodel status, awarding their high-profile " Angels " multi-year, multi-million-dollar contracts.
Gentrification of Philadelphia's neighborhoods continues into the 21st century and the city has reversed its decades-long trend of population loss.
If the trend continues, the world's urban population will double every 38 years.
Although decentralization is the current trend in Philippine local governance, the country remains a unitary state and the National Government continues to have strong influence over local government units.
The trend of urbanization continues, though not always in connection with industrialisation.
This trend continues today despite a downturn at the Appliance Park, and the area is commonly recognized as a commuter town in regards to Louisville.
This trend continues through late autumn and winter, with a marked drop in precipitation beginning in April which coincides with a gradual rise in temperature into late spring and summer.
Not unlike stamps or coins, prices for older and / or more collectible models began to spiral upwards in a trend that continues to this day.
As this trend continues, so too does the risk that markets for food will display monopolistic or oligarchical characteristics.
While consumer electronics continues in its trend of convergence, combining elements of many products, consumers face different decisions when purchasing.
Arguably, the real reason for the 934 MHz band's demise, was the lucrative sale of the band to the mobile phone industry ; the start of a trend that continues with the move from analogue to digital TV.
Many regional markets have achieved some success and the ongoing trend continues to be towards deregulation and introduction of competition.
This continues an older trend whose root was initially in the imbalance of wealth associated with the farming economy previously prevalent in the area.
If this trend continues, people in stepfamilies may make up half of the population by the next century.
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