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Because of the very high melting point of chromium, chromium thermite casting is impractical. Heating with chlorine and carbon yields chromium(III) chloride and carbon monoxide: Cr 2 O 3 + 3 Cl 2 + 3 C → 2 CrCl 3 + 3 CO. Chromates can be formed by the oxidation of chromium(III) oxide and another oxide in a basic environment: 2 Cr 2 O 3 + 4 MO ...
The Gmelin rare earths handbook lists 1522 °C and 1550 °C as two melting points given in the literature, the most recent reference [Handbook on the chemistry and physics of rare earths, vol.12 (1989)] is given with 1529 °C.
Chromium trioxide decomposes above 197 °C, liberating oxygen and eventually giving Cr 2 O 3: 4 CrO 3 → 2 Cr 2 O 3 + 3 O 2. It is used in organic synthesis as an oxidant, often as a solution in acetic acid, [9] or acetone in the case of the Jones oxidation. In these oxidations, the Cr(VI) converts primary alcohols to the corresponding ...
It is dehydrated by heating to form the green chromium(III) oxide (Cr 2 O 3), ... This red solid has a melting point of 30 °C and a boiling point of 117 °C. It can ...
Chromium oxide may refer to: Chromium(II) oxide, CrO; Chromium(III) oxide, Cr 2 O 3; Chromium dioxide (chromium(IV) oxide), CrO 2, which includes the hypothetical compound chromium(II) chromate; Chromium trioxide (chromium(VI) oxide), CrO 3; Chromium(VI) oxide peroxide, CrO 5; Mixed valence species, such as Cr 8 O 21
The five elements niobium, molybdenum, tantalum, tungsten and rhenium are included in all definitions, [3] while the widest definition, including all elements with a melting point above 2,123 K (1,850 °C), such as titanium, vanadium, zirconium, and chromium. [4]
1.201 g/cm 3 [clarification needed] Melting point: 197 °C (387 °F; 470 K) [clarification needed] ... Chromium trioxide is the anhydride of molecular chromic acid.
Chromium(II) oxide (CrO) is an inorganic compound composed of chromium and oxygen. [1] It is a black powder that crystallises in the rock salt structure. [2] Hypophosphites may reduce chromium(III) oxide to chromium(II) oxide: H 3 PO 2 + 2 Cr 2 O 3 → 4 CrO + H 3 PO 4. It is readily oxidized by the atmosphere. CrO is basic, while CrO 3 is ...