Names | |
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Other names Vanadium sesquioxide, Vanadic oxide | |
Identifiers | |
3D model (JSmol) | |
ECHA InfoCard | 100.013.847 |
PubChem CID | |
RTECS number |
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UNII | |
CompTox Dashboard (EPA) | |
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Properties | |
V2O3 | |
Molar mass | 149.881 g/mol |
Appearance | Black powder |
Density | 4.87 g/cm3 |
Melting point | 1,940 °C (3,520 °F; 2,210 K) |
Solubility in other solvents | Insoluble |
+1976.0·10−6 cm3/mol | |
Structure [1] | |
Corundum, hR30 | |
R3c (No. 167) | |
a = 547 pm α = 53.74°, β = 90°, γ = 90° | |
Thermochemistry | |
Std molar entropy (S | 98.07 J/mol·K [2] |
Std enthalpy of formation (ΔfH⦵298) | -1218.800 kJ/mol [2] |
Gibbs free energy (ΔfG˚) | -1139.052 kJ/mol [2] |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Vanadium(III) oxide is the inorganic compound with the formula V2O3. It is a black solid prepared by reduction of V2O5 with hydrogen or carbon monoxide. [3] [4] It is a basic oxide dissolving in acids to give solutions of vanadium (III) complexes. [4] V2O3 has the corundum structure. [4] It is antiferromagnetic with a critical temperature of 160 K. [5] At this temperature there is an abrupt change in conductivity from metallic to insulating. [5] This also distorts the crystal structure to a monoclinic space group: C2/c. [1]
Upon exposure to air it gradually converts into indigo-blue V2O4. [5]
In nature it occurs as the rare mineral karelianite. [6]
Inorganic chemistry deals with synthesis and behavior of inorganic and organometallic compounds. This field covers chemical compounds that are not carbon-based, which are the subjects of organic chemistry. The distinction between the two disciplines is far from absolute, as there is much overlap in the subdiscipline of organometallic chemistry. It has applications in every aspect of the chemical industry, including catalysis, materials science, pigments, surfactants, coatings, medications, fuels, and agriculture.
Vanadium is a chemical element with the symbol V and atomic number 23. It is a hard, silvery-grey, malleable transition metal. The elemental metal is rarely found in nature, but once isolated artificially, the formation of an oxide layer (passivation) somewhat stabilizes the free metal against further oxidation.
Iron(III) oxide or ferric oxide is the inorganic compound with the formula Fe2O3. It is one of the three main oxides of iron, the other two being iron(II) oxide (FeO), which is rare; and iron(II,III) oxide (Fe3O4), which also occurs naturally as the mineral magnetite. As the mineral known as hematite, Fe2O3 is the main source of iron for the steel industry. Fe2O3 is readily attacked by acids. Iron(III) oxide is often called rust, and to some extent this label is useful, because rust shares several properties and has a similar composition; however, in chemistry, rust is considered an ill-defined material, described as Hydrous ferric oxide.
Iron(II) oxide or ferrous oxide is the inorganic compound with the formula FeO. Its mineral form is known as wüstite. One of several iron oxides, it is a black-colored powder that is sometimes confused with rust, the latter of which consists of hydrated iron(III) oxide. Iron(II) oxide also refers to a family of related non-stoichiometric compounds, which are typically iron deficient with compositions ranging from Fe0.84O to Fe0.95O.
Tungsten(VI) oxide, also known as tungsten trioxide is a chemical compound of oxygen and the transition metal tungsten, with formula WO3. The compound is also called tungstic anhydride, reflecting its relation to tungstic acid H2WO4. It is a light yellow crystalline solid.
Cyanate is an anion with the structural formula [O=C=N]−, usually written OCN−. It also refers to any salt containing it, such as ammonium cyanate.
Vanadium(V) oxide (vanadia) is the inorganic compound with the formula V2O5. Commonly known as vanadium pentoxide, it is a brown/yellow solid, although when freshly precipitated from aqueous solution, its colour is deep orange. Because of its high oxidation state, it is both an amphoteric oxide and an oxidizing agent. From the industrial perspective, it is the most important compound of vanadium, being the principal precursor to alloys of vanadium and is a widely used industrial catalyst.
Antimony(III) oxide is the inorganic compound with the formula Sb2O3. It is the most important commercial compound of antimony. It is found in nature as the minerals valentinite and senarmontite. Like most polymeric oxides, Sb2O3 dissolves in aqueous solutions with hydrolysis. A mixed arsenic-antimony oxide occurs in nature as the very rare mineral stibioclaudetite.
Chromium(III) oxide is an inorganic compound with the formula Cr
2O
3. It is one of the principal oxides of chromium and is used as a pigment. In nature, it occurs as the rare mineral eskolaite.
Sodium orthovanadate is the inorganic compound with the chemical formula Na3VO4. It forms a dihydrate Na3VO4·2H2O. Sodium orthovanadate is a salt of the VO3−4 oxyanion. It is a colorless, water-soluble solid.
Vanadium oxytrichloride is the inorganic compound with the formula VOCl3. This yellow distillable liquid hydrolyzes readily in air. It is an oxidizing agent. It is used as a reagent in organic synthesis. Samples often appear red or orange owing to an impurity of vanadium tetrachloride.
Vanadium(II) oxide is the inorganic compound with the idealized formula VO. It is one of the several binary vanadium oxides. It adopts a distorted NaCl structure and contains weak V−V metal to metal bonds. VO is a semiconductor owing to delocalisation of electrons in the t2g orbitals. VO is a non-stoichiometric compound, its composition varying from VO0.8 to VO1.3.
Vanadium(III) fluoride is the chemical compound with the formula VF3. This yellow-green, refractory solid is obtained in a two-step procedure from V2O3. Similar to other transition-metal fluorides (such as MnF2), it exhibits magnetic ordering at low temperatures (e.g. V2F6.4H2O orders below 12 K).
Gallium(III) trioxide is an inorganic compound with the formula Ga2O3. It exists as several polymorphs, all of which are white, water-insoluble solids. Ga2O3 is an intermediate in the purification of gallium, which is consumed almost exclusively as gallium arsenide. The thermal conductivity of β-Ga2O3 is at least one order of magnitude lower than the other wide bandgap semiconductors, such as GaN and SiC. It is further reduced for related nanostructures which are usually used in electronic devices. Heterogeneous integration with high thermal conductivity substrates such as diamond and SiC helps heat dissipation of β-Ga2O3 electronics.
Indium(III) oxide (In2O3) is a chemical compound, an amphoteric oxide of indium.
There are three sets of Indium halides, the trihalides, the monohalides, and several intermediate halides. In the monohalides the oxidation state of indium is +1 and their proper names are indium(I) fluoride, indium(I) chloride, indium(I) bromide and indium(I) iodide.
Vanadium oxide may refer to:
Potassium pyrosulfate, or potassium disulfate, is an inorganic compound with the chemical formula K2S2O7.
Potassium azide is the inorganic compound having the formula KN3. It is a white, water-soluble salt. It is used as a reagent in the laboratory.
Nitrosyl azide is a highly labile nitrogen oxide with chemical formula N3NO.