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Chromium compounds are compounds containing the element chromium (Cr). Chromium is a member of group 6 of the transition metals. The +3 and +6 states occur most commonly within chromium compounds, followed by +2; charges of +1, +4 and +5 for chromium are rare, but do nevertheless occasionally exist. [3] [4]
The darker blue spheres represent chromium atoms outside of the polyhedra. Cr 23 C 6 is the prototypical compound of a common crystal structure, discovered in 1933 [1] as part of the chromium-carbon binary phase diagram. Over 85 known compounds adopt this structure type, [2] which can be described as a NaCl-like packing of chromium cubes and ...
Chromium is a chemical element; it has symbol Cr and atomic number 24. It is the first element in group 6. It is a steely-grey, lustrous, hard, and brittle transition metal. [10] Chromium is valued for its high corrosion resistance and hardness.
This can only be used as a very rough guide, for instance if a narrow range of wavelengths within the band 647–700 nm is absorbed, then the blue and green receptors will be fully stimulated, making cyan, and the red receptor will be partially stimulated, diluting the cyan to a greyish hue.
This is a list of common chemical compounds with chemical formulae and CAS numbers, indexed by formula.This complements alternative listing at list of inorganic compounds. ...
For example, with the Wulff–Dötz reaction an alkyne, carbon monoxide, and a chromium carbene are combined to form a chromium half-sandwich complex [8] [9] and the phenol ligand can be isolated by mild CAN oxidation. CAN is used to cleave para-methoxybenzyl and 3,4-dimethoxybenzyl ethers, which are protecting groups for alcohols.
Chromium(II) acetate hydrate, also known as chromous acetate, is the coordination compound with the formula Cr 2 (CH 3 CO 2) 4 (H 2 O) 2. This formula is commonly abbreviated Cr 2 (OAc) 4 (H 2 O) 2 . This red-coloured compound features a quadruple bond .
The primary chromium ore is the mixed metal oxide chromite, FeCr 2 O 4, found as brittle metallic black crystals or granules. Chromite ore is heated with a mixture of calcium carbonate and sodium carbonate in the presence of air. The chromium is oxidized to the hexavalent form, while the iron forms iron(III) oxide, Fe 2 O 3: