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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+
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 ...
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. [21]
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:
A 3–10% solution of potassium hydroxide (KOH) gives a color change in some species of mushrooms: In Agaricus, some species such as A. xanthodermus turn yellow with KOH, many have no reaction, and A. subrutilescens turns green. Distinctive change occurs for some species of Cortinarius and boletes
3. Unlike the classic thermite reaction involving iron oxides, the chromium oxide thermite creates few or no sparks, smoke or sound, but glows brightly. 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
Next, thrust in an inward and upward motion on the diaphragm. This will force air out of the lungs and remove the blockage. Repeat these abdominal thrusts up to five times, the doctor advised.
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.