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Lanthanites are frequently found as secondary minerals formed by the weathering of other minerals and occur as scales or tabular crystals. Originally identified at Bastnäs , Sweden , [ 9 ] they have subsequently been found in New Zealand , [ 10 ] Japan , [ 11 ] Madagascar , [ 12 ] Wales , [ 13 ] China , [ 14 ] France , [ 15 ] Germany , [ 16 ...
This list is sorted by boiling point of gases in ascending order, but can be sorted on different values. "sub" and "triple" refer to the sublimation point and the triple point, which are given in the case of a substance that sublimes at 1 atm; "dec" refers to decomposition. "~" means approximately.
When it reacts with water, lanthanum hydroxide is formed: [37] a lot of heat is evolved in the reaction and a hissing sound is heard. Lanthanum hydroxide will react with atmospheric carbon dioxide to form the basic carbonate. [38] Lanthanum fluoride is insoluble in water and can be used as a qualitative test for the presence of La 3+.
Lanthanide metals react exothermically with hydrogen to form LnH 2, dihydrides. [1] With the exception of Eu and Yb, which resemble the Ba and Ca hydrides (non-conducting, transparent salt-like compounds),they form black pyrophoric, conducting compounds [6] where the metal sub-lattice is face centred cubic and the H atoms occupy tetrahedral sites. [1]
Complexation with monodentate ligands is generally weak because it is difficult to displace water molecules from the first coordination sphere. Stronger complexes are formed with chelating ligands because of the chelate effect, such as the tetra-anion derived from 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid .
Lutetium compounds are compounds formed by the lanthanide metal lutetium (Lu). In these compounds, lutetium generally exhibits the +3 oxidation state, such as LuCl 3, Lu 2 O 3 and Lu 2 (SO 4) 3. [1] Aqueous solutions of most lutetium salts are colorless and form white crystalline solids upon drying, with the common exception of the iodide.
Chemical weathering takes place when water, oxygen, carbon dioxide, and other chemical substances react with rock to change its composition. These reactions convert some of the original primary minerals in the rock to secondary minerals, remove other substances as solutes, and leave the most stable minerals as a chemically unchanged resistate .
Praseodymium(IV) oxide can be produced by boiling Pr 6 O 11 in water or acetic acid: [16] Pr 6 O 11 + 3 H 2 O → 4 PrO 2 + 2 Pr(OH) 3. Praseodymium(III,IV) oxide is the most stable form of the praseodymium oxides at ambient temperature and pressure. [17] It is soluble in water [18] and has a cubic fluorite structure. [19]