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Red iron(III) oxide (Fe 2 O 3, commonly known as rust) is the most common iron oxide used in thermite. [ 14 ] [ 15 ] [ 16 ] Black iron(II,III) oxide (Fe 3 O 4 , magnetite ) also works. [ 17 ] Other oxides are occasionally used, such as MnO 2 in manganese thermite, Cr 2 O 3 in chromium thermite, SiO 2 (quartz) in silicon thermite, or copper(II ...
For some metals, carbothermic reactions do not afford the metal, but instead give the metal carbide. This behavior is observed for titanium, hence the use of the chloride process. Carbides also form upon high temperature treatment of Cr 2 O 3 with carbon. For this reason, aluminium is employed as the reducing agent.
The most common example of roasting is the oxidation of metal sulfide ores. The metal sulfide is heated in the presence of air to a temperature that allows the oxygen in the air to react with the sulfide to form sulfur dioxide gas and solid metal oxide. The solid product from roasting is often called "calcine".
Measures to protect against laboratory accidents include safety training and enforcement of laboratory safety policies, safety review of experimental designs, the use of personal protective equipment, and the use of the buddy system for particularly risky operations. In many countries, laboratory work is subject to health and safety legislation.
The initial discovery came in 1997 when Cambridge University researchers immersed small samples of certain oxides in baths of molten salt and reduced the oxide with electric current. The cathode uses powdered metal oxide. The anode is made of carbon. The molten salt at 1,000 °C (1,830 °F) is the electrolyte.
While typically hopcalite catalysts are prepared by calcining intimate mixtures of oxides and carbonates, [4] various techniques have been employed for producing hopcalites in the laboratory and on an industrial scale, such as physical mixing of the (finely divided) metal oxides, co-precipitation of the metal oxides from metal salt solutions (see salts), thermal decomposition of mixtures of ...
Sodium methoxide is prepared by treating methanol with sodium: 2 Na + 2 CH 3 OH → 2 CH 3 ONa + H 2. The reaction is so exothermic that ignition is possible. The resulting solution, which is colorless, is often used as a source of sodium methoxide, but the pure material can be isolated by evaporation followed by heating to remove residual methanol.
Aluminium oxide is used for its hardness and strength. Its naturally occurring form, corundum, is a 9 on the Mohs scale of mineral hardness (just below diamond). It is widely used as an abrasive, including as a much less expensive substitute for industrial diamond. Many types of sandpaper use aluminium oxide crystals.