Lanthanum



Gan Le Lanthanum   Protons number: 57 **
 * 
 * Electrons number: 57 **
 * Neutrons number 82 **
 * Atomic Number: 57 **
 * Atomic Symbol: La **
 * Atomic Weight: 138.9055 **

 (Greek //lanthanein//: to lie hidden) Mosander in 1839 extracted lanthana from impure cerium nitrate and recognized the new element.
 * Electron Configuration: [Xe] ** 6s25d1
 * Atomic Radius: **187.7 pm
 * Melting Point: **<span style="font-family: 'Times New Roman','serif'; font-size: 12pt; mso-fareast-font-family: 'Times New Roman';">918 Celsius
 * <span style="font-family: 'Times New Roman','serif'; font-size: 12pt; mso-fareast-font-family: 'Times New Roman';">Boiling Point: **<span style="font-family: 'Times New Roman','serif'; font-size: 12pt; mso-fareast-font-family: 'Times New Roman';">1897 Celsius
 * <span style="font-family: 'Times New Roman','serif'; font-size: 18pt; mso-fareast-font-family: 'Times New Roman';">Oxidation States: **<span style="font-family: 'Times New Roman','serif'; font-size: 18pt; mso-fareast-font-family: 'Times New Roman';">2
 * <span style="font-family: 'Times New Roman','serif'; font-size: 18pt; mso-fareast-font-family: 'Times New Roman';">History **

Lanthanum was isolated in relatively pure form in 1923. Iron exchange and solvent extraction techniques have led to much easier isolation of the so-called "rare-earth" elements. <span style="font-family: 'Times New Roman','serif'; font-size: 12pt; mso-fareast-font-family: 'Times New Roman';">Lanthanum is found in rare-earth minerals such as cerite, monazite, allanite, and bastnasite.
 * <span style="font-family: 'Times New Roman','serif'; font-size: 18pt; mso-fareast-font-family: 'Times New Roman';">Sources **

Properties
Lanthanum is silvery white, malleable, ductile, and soft. It is the most reactive of the rare-earth metals. Cold water attacks lanthanum slowly, while hot water attacks it much more rapidly. The metal reacts directly with elemental carbon, nitrogen,boron, selenium, silicon, phosphorus, sulfur, and with halogens.

Isotopes [[image:La1Se1-12031311.jpg width="240" height="180"]]
Natural lanthanum is a mixture of two stable isotopes, 138La and 139La. Twenty three other radioactive isotopes are recognized.

Uses
Rare-earth compounds containing lanthanum are extensively used in carbon lighting applications, especially by the motion picture industry for studio lighting and projection. Small amounts of lanthanum, as an additive, can be used to produce nodular cast iron.

Handling
Lanthanum and its compounds have a low toxicity rating; therefore,becareful when handling them.

Costs
The metal costs about $5/g. [|**http://www.lenntech.com/periodic/elements/la/htm**] [|**http://www.flw.com/datatools/periodic/e_model/57.gif**] [|**http://www.wisegeek.com/what-is-lanthanum.htm**] [|**http://www.americanelements.com/ingot.jpg**] [|**http://www.hobart.k12.in.us/ksms/PeriodicTable/About%20Graphics/lanthanum.jpg**] [|**http://en.wikipedia.org/wiki/Lutetium**]
 * All the information is taking from the sources below:**