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21-570: Dilala is a commune of the city of Kolwezi in the Democratic Republic of the Congo . This Democratic Republic of the Congo location article is a stub . You can help Misplaced Pages by expanding it . Kolwezi Kolwezi or Kolwesi is the capital city of Lualaba Province in the south of the Democratic Republic of the Congo , west of Likasi . It has an airport and a railway to Lubumbashi . Just outside of Kolwezi there

42-419: A chemical reagent. A common and cheap reducing agent is carbon in the form of coke . The most prominent example is that of iron ore smelting . Many reactions are involved, but the simplified equation is usually shown as: Some metal oxides dissolve in the presence of reducing agents, which can include organic compounds. Reductive dissolution of ferric oxides is integral to geochemical phenomena such as

63-432: A deficiency of oxygen, the monoxide is produced: With excess oxygen, the dioxide is the product, the pathway proceeds by the intermediacy of carbon monoxide: Elemental nitrogen ( N 2 ) is difficult to convert to oxides, but the combustion of ammonia gives nitric oxide, which further reacts with oxygen: These reactions are practiced in the production of nitric acid , a commodity chemical. The chemical produced on

84-430: A few noble gases. The pathways for the formation of this diverse family of compounds are correspondingly numerous. Many metal oxides arise by decomposition of other metal compounds, e.g. carbonates, hydroxides, and nitrates. In the making of calcium oxide, calcium carbonate (limestone) breaks down upon heating, releasing carbon dioxide: The reaction of elements with oxygen in air is a key step in corrosion relevant to

105-448: A source of hydroelectric power and a reservoir of water for the mining activities. Kolwezi and its cobalt mining economy was profiled in the May 24, 2021 edition of The New Yorker by writer Nicolas Niarchos. The acute financial and environmental impacts on the city and its economy were highlighted in the article. The rapid growth of the cobalt mining industry has caused a recent surge in

126-520: Is a more complex molecular oxide with a deceptive name, the real formula being P 4 O 10 . Tetroxides are rare, with a few more common examples being ruthenium tetroxide , osmium tetroxide , and xenon tetroxide . Reduction of metal oxide to the metal is practiced on a large scale in the production of some metals. Many metal oxides convert to metals simply by heating, (see Thermal decomposition ). For example, silver oxide decomposes at 200 °C: Most often, however, metals oxides are reduced by

147-511: Is located on the eastern edge of the city. Kolwezi has several medical clinics and hospitals along with dozens of primary and secondary schools. Is an upscale neighborhood located in the center of Kolwezi. The area is home to several foreign workers and a number of guest houses. Manika Stadium is located in the Dilala neighborhood. Kolwezi's Central Train Station is located on the eastern edge of

168-491: Is set on an arid plain in the south of the Democratic Republic of Congo . Upon its establishment in 1937 by the Union Minière du Haut-Katangahe, the company cleared the land of the acacias and miombo trees that once grew atop Kolwezi’s rich mineral deposits. They subsequently built a simple low-rise town across the area’s rolling hills, with wide streets and bungalows for Europeans, whose neighborhoods were segregated from

189-617: Is the static inverter plant of the HVDC Inga-Shaba . The population is approximately 573,000. Before the creation of Lualaba province in 2015 Kolwezi had two territories attached to it and the whole was known as the Kolwezi District . The settlement was created in 1938 to be the headquarters for the western mining group of the Union Minière du Haut Katanga . In 1971 it obtained city status and consisted of

210-686: The iron cycle . Because the M-O bonds are typically strong, metal oxides tend to be insoluble in solvents, though they may be attacked by aqueous acids and bases. Dissolution of oxides often gives oxyanions . Adding aqueous base to P 4 O 10 gives various phosphates . Adding aqueous base to MoO 3 gives polyoxometalates . Oxycations are rarer, some examples being nitrosonium ( NO ), vanadyl ( VO ), and uranyl ( UO 2+ 2 ). Of course many compounds are known with both oxides and other groups. In organic chemistry , these include ketones and many related carbonyl compounds. For

231-608: The cathode in electrolysis) or other anions (a negatively charged ion). Iron silicate , Fe 2 SiO 4 , the mineral fayalite , is one of many examples of a ternary oxide. For many metal oxides, the possibilities of polymorphism and nonstoichiometry exist as well. The commercially important dioxides of titanium exists in three distinct structures, for example. Many metal oxides exist in various nonstoichiometric states. Many molecular oxides exist with diverse ligands as well. For simplicity sake, most of this article focuses on binary oxides. Oxides are associated with all elements except

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252-609: The cities of Lubumbashi and Dilolo . The city of Kolwezi has one of the main railway stations in Congo, from where mineral loads and passengers board every day. The station receives trains from the Benguela railway . The Kolwezi Airport serves Kolwezi and the surrounding area. The airport is located about 6 km (4 mi) south of Kolwezi. Oxide Oxides are extraordinarily diverse in terms of stoichiometries (the measurable relationship between reactants and chemical equations of an equation or reaction) and in terms of

273-518: The city's population. Kolwezi has a monsoon-influenced humid subtropical climate ( Köppen climate classification Cwa ). The city has a dry-winter humid subtropical climate (Cwa, according to the Köppen climate classification), with warm rainy summers and pleasant, dry winters, with most rainfall occurring during summer and early autumn. Annual average rainfall is 45.8 inches. The city is crossed by Transafrican Highway 9 (TAH 9), which connects it to

294-638: The city. The government of Zaire asked Belgium , France, Morocco and the United States to restore order. The 2e REP , an elite paratroopers unit of the French Foreign Legion , were sent in to drive out the rebels and rescue any hostages. The Belgian army also deployed a force of some 750 Paracommando Regiment paratroopers and moved out just over 1,800 Europeans to other cities in the region. 700 Africans, including 250 rebels, 170 European hostages and 6 paratroopers died. Kolwezi

315-727: The commercial use of iron especially. Almost all elements form oxides upon heating with oxygen atmosphere. For example, zinc powder will burn in air to give zinc oxide: The production of metals from ores often involves the production of oxides by roasting (heating) metal sulfide minerals in air. In this way, MoS 2 ( molybdenite ) is converted to molybdenum trioxide , the precursor to virtually all molybdenum compounds: Noble metals (such as gold and platinum ) are prized because they resist direct chemical combination with oxygen. Important and prevalent nonmetal oxides are carbon dioxide and carbon monoxide . These species form upon full or partial oxidation of carbon or hydrocarbons. With

336-563: The communes of Dilala and Manika . In 1976 the territories of Lubudi and Mutshatsha , both previously part of Lualaba District , were attached to it to form the Kolwezi District (districts were called sub-regions at the time). In the 2015 repartitioning this was undone, the two territories and the city proper became separate parts of Lualaba province with the city as capital of the new province. On Saturday, 13 May 1978, ex- Katangese soldiers supported by Angola occupied

357-777: The largest scale industrially is sulfuric acid . It is produced by the oxidation of sulfur to sulfur dioxide , which is separately oxidized to sulfur trioxide : Finally the trioxide is converted to sulfuric acid by a hydration reaction : Oxides have a range of structures, from individual molecules to polymeric and crystalline structures. At standard conditions, oxides may range from solids to gases. Solid oxides of metals usually have polymeric structures at ambient conditions. Although most metal oxides are crystalline solids, many non-metal oxides are molecules. Examples of molecular oxides are carbon dioxide and carbon monoxide . All simple oxides of nitrogen are molecular, e.g., NO, N 2 O, NO 2 and N 2 O 4 . Phosphorus pentoxide

378-472: The neighborhood with train service to Likasi and Lubumbashi . Kolwezi is an important mining centre for copper and cobalt . There are also uranium , radium , oxide ores, and lime deposits. The Musonoi mine is a set of open-cut pits near Kolwezi from which copper and other metals have been extracted since the 1940s. The nearby Lake Nzilo was created by damming the Lualaba River to provide

399-509: The poorly built ones where Congolese workers lived. The N39 highway runs through the center of town on a northwest-southeast axis. Large open pit cobalt mines are located to the west and north of the city center. Rond Point de L'Indépendance is the traditional center of the city with more formally laid out neighborhoods located to the west of the traffic circle. The center of the city contains administrative offices, dozens of guesthouses and hotels, banks and restaurants. Mutoshi Technical Institute

420-462: The structures of each stoichiometry. Most elements form oxides of more than one stoichiometry. A well known example is carbon monoxide and carbon dioxide . This applies to binary oxides, that is, compounds containing only oxide and another element. Far more common than binary oxides are oxides of more complex stoichiometries. Such complexity can arise by the introduction of other cations (a positively charged ion, i.e. one that would be attracted to

441-399: The transition metals, many oxo complexes are known as well as oxyhalides . The chemical formulas of the oxides of the chemical elements in their highest oxidation state are predictable and are derived from the number of valence electrons for that element. Even the chemical formula of O 4 , tetraoxygen , is predictable as a group 16 element . One exception is copper , for which

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