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The Pourbaix diagram for chromium in pure water, perchloric acid, or sodium hydroxide [1] [2] 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 ...
The chromium(II) hydride monomer, is both thermodynamically and kinetically unstable towards autopolymerization at ambient temperature, and so cannot be concentrated. Nevertheless, molecules of CrH 2 and Cr 2 H 4 have been isolated in solid gas matrices. [1] Cr is the second simplest molecular chromium hydride (after Chromium(I) hydride).
The use of chrome yellow has since declined due to environmental and safety concerns and was replaced by organic pigments or other alternatives that are free from lead and chromium. Other pigments that are based around chromium are, for example, the deep shade of red pigment chrome red, which is simply lead chromate with lead(II) hydroxide ...
Chromium(II) chloride (chromous chloride) – CrCl 2; Chromium(II) sulfate – CrSO 4; Chromium(III) chloride – CrCl 3; Chromium(III) nitrate – Cr(NO 3) 3; Chromium(III) oxide – Cr 2 O 3; Chromium(III) sulfate – Cr 2 (SO 4) 3; Chromium(III) telluride – Cr 2 Te 3; Chromium(IV) oxide – CrO 2; Chromium pentafluoride – CrF 5; Chromyl ...
The hydrogen content of chromium hydride is between zero and a few hundred parts per million in weight for plain chromium-hydrogen alloys. These values vary depending on alloying elements, such as iron, manganese, vanadium, titanium [12] and so on.
Substance Formula 0 °C 10 °C 20 °C 30 °C 40 °C 50 °C 60 °C 70 °C 80 °C 90 °C 100 °C Barium acetate: Ba(C 2 H 3 O 2) 2: 58.8: 62: 72: 75: 78.5: 77: 75
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:
Chromium(III) hydroxide is a gelatinous green inorganic compound with the chemical formula Cr(OH) 3. It is a polymer with an undefined structure and low solubility. It is amphoteric, dissolving in both strong alkalis and strong acids. [2] In alkali: Cr(OH) 3 + OH − → CrO − 2 + 2 H 2 O In acid: Cr(OH) 3 (OH 2) 3 + 3 H + → Cr(OH 2) 6 3+