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Lanthanum Facts

Lanthanum Facts
Lanthanum (La) has an atomic number of fifty-seven, and the same number of protons in the nucleus of one of its atoms. This silvery-white, soft metal is one of the most highly reactive of all of the rare-earth metals.
Interesting Lanthanum Facts:
Lanthanum was discovered by a Swedish scientist, Carl Gustaf Mosander, in 1839.
It wasn't until 1923, though, that a fairly pure sample of the element was produced.
Mosander's discovery of lanthanum from the salts of heated cerium nitrate was made possible by the fact that lanthanum is the strongest base of all trivalent lanthanides.
It is the first member of the periodic table's lanthanides series.
Despite its being a member of the rare earth metals—so named due to their comparative abundance to the more common metals—lanthanum is a fairly abundant element.
It is concentrated at about thirty-two parts per million in the Earth's crust.
What does contribute to lanthanum being a rare earth metal is the difficulty and expense of mining the substance from its two primary ores, monazite and bastnasite.
Due to its readily oxidizing characteristic, pure lanthanum is only used for research purposes.
It is highly malleable and can easily be cut with a knife.
There are thirty-eight known isotopes of lanthanum, but only two are believed to occur in nature.
Of those two naturally occurring isotopes, La-139 is stable and La-138 is radioactive.
The two most stable radioisotopes of lanthanum have half-lives of more than 60,000 years, with La-138 having a half-life of 105,000,000,000 years.
Lanthanum's remaining radioactive isotopes have half-lives of less than twenty-four hours and most of those having half-lives of less than one minute.
In the late 1800s, lanthanum was used to produce glowing mantles in commercial lanterns, and the proprietary mixture of chemicals gave off a green light.
Lanthanum has been used in a variety of applications since its discovery, including vacuum tubes, hydrogen alloys, medications, and molecular biology.
Today, lanthanum is used as a component of nickel-metal hydride batteries, whose most important commercial use is in hybrid cars.

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