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The relatively complicated formula - [Cr(H 2 O) 6](NO 3) 3 •3H 2 O - betray a simple structure of this material. The chromium centers are bound to six aquo ligands, and the remaining volume of the solid is occupied by three nitrate anions and three molecules of water of crystallization. [3]
Chromium(III) hydroxide (Cr(OH) 3) is amphoteric, dissolving in acidic solutions to form [Cr(H 2 O) 6] 3+, and in basic solutions to form [Cr(OH) 6] 3−. It is dehydrated by heating to form the green chromium(III) oxide (Cr 2 O 3), a stable oxide with a crystal structure identical to that of corundum. [6]
The method is illustrated by the route to β-Cu(NO 3) 2: Cu + 2 N 2 O 4 → Cu(NO 3) 2 + 2 NO. Many metals, metal halides, and metal carbonyls undergo similar reactions, but the product formulas can be deceptive. For example from chromium one obtains Cr(NO 3) 3 (N 2 O 4) 2, which was shown to be the salt (NO +) 2 [Cr(NO 3) 5] 2-. [15]
Chromium azide formation has been investigated from chromium salts and sodium azide. It was separated in 1922 through the evaporation of a dry crystalline chromium(III) nitrate solution in absolute alcohol with sodium azide. [1]
Chromium nitride is a chemical compound of chromium and nitrogen with the formula CrN. It is very hard, and is extremely resistant to corrosion.It is an interstitial compound, with nitrogen atoms occupying the octahedral holes in the chromium lattice: [2] as such, it is not strictly a chromium(III) compound nor does it contain nitride ions (N 3−).
A Delaware woman who was reported missing last week after she didn't show up to work for several days was found dismembered in a car over the weekend, police said.
The Parisians Pannetier and Binet first prepared the transparent hydrated form of Cr 2 O 3 in 1838 via a secret process, sold as a pigment. [6] It is derived from the mineral chromite, (Fe,Mg)Cr 2 O 4. The conversion of chromite to chromia proceeds via Na 2 Cr 2 O 7, which is reduced with sulfur at high temperatures: [7] Na 2 Cr 2 O 7 + S → ...
MINEOLA, N.Y. — A Republican official who oversees Nassau County on New York's Long Island has seemingly refused to lower flags to half-staff in memory of the late Democratic President Jimmy ...