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Curium(III) oxide is a compound composed of curium and oxygen with the chemical formula Cm 2 O 3. It is a crystalline solid with a unit cell that contains two curium atoms and three oxygen atoms. The simplest synthesis equation involves the reaction of curium(III) metal with O 2−: 2 Cm 3+ + 3 O 2−---> Cm 2 O 3. [1]
Metallic curium is annealed in air or in an oxygen atmosphere: [1] Cm + O 2 → CmO 2. Curium(III) hydroxide and curium(III) oxalate are also usually used for this purpose: Cm(OH) 4 → CmO 2 + 2H 2 O Cm(C 2 O 4) 2 → CmO 2 + 2CO 2 + 2CO. Another way is the reaction of curium(III) oxide in an oxygen atmosphere at 650 °C: [2] 2Cm 2 O 3 + O 2 ...
Curium readily reacts with oxygen forming mostly Cm 2 O 3 and CmO 2 oxides, [1] but the divalent oxide CmO is also known. [2] Black CmO 2 can be obtained by burning curium oxalate (Cm 2 (C 2 O 4) 3), nitrate (Cm(NO 3) 3), or hydroxide in pure oxygen. [3] [4] Upon heating to 600–650 °C in vacuum (about 0.01 Pa), it transforms into the whitish ...
The main disadvantage of the stoichiometric ceria cycle lies in the fact that the reduction reaction temperature of cerium(IV) oxide is at the same range of the melting temperature (1,687–2,230 °C) of cerium(IV) oxide (), [5] which in the end results in some melting and sublimation of the material, which can produce reactor failures such as ...
Rather than combustion, organisms rely on elaborate sequences of electron-transfer reactions, often coupled to proton transfer. The direct reaction of O 2 with fuel is precluded by the oxygen reduction reaction, which produces water and adenosine triphosphate. Cytochrome c oxidase affects the oxygen reduction reaction by binding O 2 in a heme ...
The difference in the emission rates of the metal and the oxide is due mainly to the alpha, neutron reaction with the oxygen-18 and oxygen-17 present in the oxide. The normal amount of oxygen-18 present in the natural form is 0.204% while that of oxygen-17 is 0.037%. The reduction of the oxygen-17 and oxygen-18 present in the plutonium dioxide ...
In thermolysis, water molecules split into hydrogen and oxygen. For example, at 2,200 °C (2,470 K; 3,990 °F) about three percent of all H 2 O are dissociated into various combinations of hydrogen and oxygen atoms, mostly H, H 2, O, O 2, and OH. Other reaction products like H 2 O 2 or HO 2 remain minor. At the very high temperature of 3,000 ...
Of the two half reactions, the oxidation step is the most demanding because it requires the coupling of 4 electron and proton transfers and the formation of an oxygen-oxygen bond. This process occurs naturally in plants photosystem II to provide protons and electrons for the photosynthesis process and release oxygen to the atmosphere, [ 1 ] as ...