SUMMARY / RELATED TOPICS

Iron(III) oxide-hydroxide

Iron oxide-hydroxide or ferric oxyhydroxide is the chemical compound of iron and hydrogen with formula FeO. The compound is encountered as one of its hydrates, FeO·nH2O; the monohydrate FeO·H2O is referred as iron hydroxide Fe3, hydrated iron oxide, yellow iron oxide, or Pigment Yellow 42. Anhydrous ferric oxyhydroxide FeOOH occurs as four different minerals denoted by the Greek letters α, β, γ and δ. Goethite, α-FeO, has been used as an ocher pigment since prehistoric times. Akaganeite is the β polymorph, formed by weathering and noted for its presence in some meteorites and the lunar surface; however it has been determined that it must contain some chloride ions to stabilize its structure, so that its more accurate formula is FeO0.8331.167Cl0.167 or Fe6O57Cl. Lepidocrocite, the γ polymorph, is encountered as rust on the inside of steel water pipes and tanks. Feroxyhyte is formed under the high pressure conditions of sea and ocean floors, being thermodynamically unstable with respect to the α polymorph at surface conditions.

Siderogel is a occurring colloidal form of iron oxide-hydroxide. Goethite and lepidocrocite, both crystallizing in orthorhombic system, are the most common forms of iron oxyhydroxide and the most important mineral carriers of iron in soils. Iron oxyhydroxide is the main component of other minerals and mineraloids: Limonite is a occurring mixture of goethite, lepidocrocite and clay minerals. Ferrihydrite is an amorphous or nanocrystalline hydrated mineral FeOOH•1.8H2O but with variable hydration. The color of iron oxyhydroxide ranges from yellow through dark-brown to black, depending on the degree of hydration, particle size and shape, crystal structure; the crystal structure of β-FeOOH is that of hollandite or BaMn8O16. The unit cell is tetragonal with a=1.048 and c=0.3023 nm, contains eight formula units of FeOOH. Its dimensions are about 500 × 50 × 50 nm. Twinning produces particles with the shape of hexagonal stars. On heating, β-FeOOH decomposes and recrystallizes as α-Fe2O3. Limonite, a mixture of various hydrates and polymorphs of ferric oxyhydroxide, is one of the three major iron ores, having been used since at least 2500 BCE.

Yellow iron oxide, or Pigment Yellow 42, is Food and Drug Administration approved for use in cosmetics and is used in some tattoo inks. Iron oxide-hydroxide is used in aquarium water treatment as a phosphate binder. Iron oxide-hydroxide nanoparticles have been studied as possible adsorbents for lead removal from aquatic media. Iron oxyhydroxide precipitates from solutions of iron salts at pH between 6.5 and 8.. Thus the oxyhydroxide can be obtained in the lab by reacting an iron salt, such as ferric chloride or ferric nitrate, with sodium hydroxide: FeCl3 + 3 NaOH → Fe3 + 3 NaCl Fe3 + 3 NaOH → Fe3 + 3 NaNO3In fact, when dissolved in water, pure FeCl3 will hydrolyze to some extent, yielding the oxyhydroxide and making the solution acidic: FeCl3 + 2 H2O ↔ FeOOH + 3 HClTherefore, the compound can be obtained by the decomposition of acidic solutions of iron chloride held near the boiling point for days or weeks: FeCl3 + 2 H2O → FeOOH + 3 HCl The oxyhydroxide prepared from ferric chloride is the β polymorph in the form of thin needles.

The oxyhydroxide can be produced by a solid-state transformation from iron chloride tetrahydrate FeCl2·4H2O. The compound readily forms when iron hydroxide is exposed to air: 4Fe2 + O2 → 4 FeOOH + 2 H2OThe iron hydroxide can be oxidized by hydrogen peroxide in the presence of an acid: 2Fe2 + H2O2 → 2 Fe3 The risk and safety phrases for iron oxides are R36, R37, R38, S26, S36. Rust Iron oxide Yellow boy, a yellow precipitate when acidic runoff such as mine waste, is neutralised

South Shore Bungalow Historic District

The South Shore Bungalow Historic District is a residential historic district in the South Shore neighborhood of Chicago, Illinois. The district contains 229 Chicago bungalows and twenty other residential buildings built between 1911 and 1930; as homes became more accessible to families in early 20th century Chicago, thousands of bungalows were built to meet the housing demand. While bungalows were affordable due to their uniform designs, their builders changed details such as color and entrance position to keep each home unique; the South Shore bungalows were among the first built in the city, as South Shore was a popular neighborhood when the bungalow boom began, the district contains many 1910s stucco bungalows. The district was added to the National Register of Historic Places on December 10, 2008

Bilistiche

Bilistiche or Belistiche was a Hellenistic courtesan of uncertain origin. According to Pausanias, she was a Macedonian, she synoris horse races in the 264 BC Olympic Games. She was deified by him as Aphrodite Bilistiche. According to Clement of Alexandria, she was buried under the shrine of Sarapis in Alexandria. Chris Bennett - Bilistiche Kosmetatou, Elizabeth. "Bilistiche and the Quasi-Institutional Status of Ptolemaic Royal Mistress". Archiv für Papyrusforschung und verwandte Gebiete. Volume 50, Issue 1, Pages 18–36, ISSN 1867-1551, ISSN 0066-6459, 2004. Doi:10.1515/apf.2004.50.1.18