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Copper nitrate, in combination with acetic anhydride, is an effective reagent for nitration of aromatic compounds, known as the Menke nitration. [17] Hydrated copper nitrate adsorbed onto clay affords a reagent called "Claycop". The resulting blue-colored clay is used as a slurry, for example for the oxidation of thiols to disulfides.
Calcium carbonate (limestone or chalk) decomposes into calcium oxide and carbon dioxide when heated. The chemical reaction is as follows: CaCO 3 → CaO + CO 2 The reaction is used to make quick lime, which is an industrially important product. Another example of thermal decomposition is 2Pb(NO 3) 2 → 2PbO + O 2 + 4NO 2.
It can be formed by heating copper in air at around 300–800 °C: 2 Cu + O 2 → 2 CuO. For laboratory uses, copper(II) oxide is conveniently prepared by pyrolysis of copper(II) nitrate or basic copper(II) carbonate: [4] 2 Cu(NO 3) 2 → 2 CuO + 4 NO 2 + O 2 (180°C) Cu 2 (OH) 2 CO 3 → 2 CuO + CO 2 + H 2 O. Dehydration of cupric hydroxide ...
For example, the thermal decomposition of some metal nitrates generates NO 2: [14] Pb(NO 3) 2 → PbO + 2 NO 2 + 1 ⁄ 2 O 2. Alternatively, dehydration of nitric acid produces nitronium nitrate... 2 HNO 3 → N 2 O 5 + H 2 O 6 HNO 3 + 1 ⁄ 2 P 4 O 10 → 3 N 2 O 5 + 2 H 3 PO 4...which subsequently undergoes thermal decomposition: N 2 O 5 → ...
The oxygen in the ore binds to carbon at high temperatures, as the chemical potential energy of the bonds in carbon dioxide (CO 2) is lower than that of the bonds in the ore. Sulfide ores such as those commonly used to obtain copper, zinc or lead, are roasted before smelting in order to convert the sulfides to oxides, which are more readily ...
The formation free energy of carbon dioxide (CO 2) is almost independent of temperature, while that of carbon monoxide (CO) has negative slope and crosses the CO 2 line near 700 °C. According to the Boudouard reaction , carbon monoxide is the dominant oxide of carbon at higher temperatures (above about 700 °C), and the higher the temperature ...
Carbothermal reactions produce carbon monoxide (CO) and sometimes carbon dioxide (CO 2). The facility of these conversions is attributable to the entropy of reaction: two solids, the metal oxide (and flux) and carbon, are converted to a new solid (metal) and a gas (CO x), the latter having high entropy.
Smelting involves thermal reactions in which at least one product is a molten phase. Metal oxides can then be smelted by heating with coke or charcoal (forms of carbon), a reducing agent that liberates the oxygen as carbon dioxide leaving a refined mineral.