| Vanadium(V) oxide | |
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| IUPAC name | Vanadium(V) oxide |
| Other names | Vanadium pentoxide, vanadic anhydride, divanadium pentoxide |
| Identifiers | |
| CAS number | [1314-62-1] |
| Properties | |
| Molecular formula | V2O5 |
| Molar mass | 181. IUPAC Nomenclature is a system of naming Chemical compounds and of describing the science of Chemistry in general CAS registry numbers are unique numerical identifiers for Chemical compounds Polymers biological sequences mixtures and Alloys They are also referred to A chemical formula is a way of expressing information about the Atoms that constitute a particular Chemical compound, and how the relationship between those atoms changes Molar mass, symbol M, is the Mass of one mole of a substance ( Chemical element or Chemical compound) 88 g/mol |
| Appearance | Orange-yellow solid |
| Density | 3. The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different 357 g/cm³, solid |
| Melting point |
690 °C (963 K) |
| Boiling point |
1750 °C (2020 K) |
| Solubility in water | 0. The melting point of a solid is the temperature range at which it changes state from solid to Liquid. The boiling point of a liquid is the temperature at which the Vapor pressure of the liquid equals the environmental pressure surrounding the liquid Solubility is the characteristic Physical property referring to the ability of a given substance the Solute, to dissolve in a Solvent. Water is a common Chemical substance that is essential for the survival of all known forms of Life. 8 g/100 mL (20 °C) |
| Hazards | |
| EU classification | Toxic (T) |
| R-phrases | R20, R22, R37, R48 R23, R51, R53 |
| S-phrases | S36, S37, S38, S45, S61 |
| Related compounds | |
| Other anions | Vanadium oxytrichloride |
| Other cations | Niobium(V) oxide Titanium(IV) oxide Chromium trioxide |
| Related V compounds | Vanadium(IV) oxide Vanadium(V) fluoride |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references |
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Vanadium(V) oxide (vanadia) is the chemical compound with the formula V2O5. Council Directive 67/548/EEC of 27 June 1967 on the approximation of laws regulations and administrative provisions relating to the classification packaging and labelling R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. An ion is an Atom or Molecule which has lost or gained one or more Valence electrons giving it a positive or negative electrical charge Vanadium oxytrichloride is the Inorganic compound with the formula VOCl3 An ion is an Atom or Molecule which has lost or gained one or more Valence electrons giving it a positive or negative electrical charge Niobium pentoxide, is the Chemical compound with the formula Nb 2 O 5 Titanium dioxide, also known as titanium(IV oxide or titania, is the naturally occurring Oxide of Titanium, chemical formula Ti[[oxygen The acid Anhydride of Chromic acid, CrO3 is chromium trioxide or chromium(VI oxide; industrially this compound is sometimes sold as " Vanadium(IV oxide is the chemical compound VO2 It is formed in the contact process from V2O5 which acts as a Catalyst. In Chemistry, the standard state of a material is its state at 1 bar (100 Kilopascals exactly A chemical compound is a substance consisting of two or more different elements chemically bonded together in a fixed proportion by Mass. A chemical formula is a way of expressing information about the Atoms that constitute a particular Chemical compound, and how the relationship between those atoms changes Commonly known as vanadium pentoxide, this orange solid is the most important compound of vanadium. Traditionally inorganic compounds are considered to be of mineral not biological origin Vanadium (vəˈneɪdiəm is a Chemical element that has the symbol V and Atomic number 23 Upon heating it reversibly loses oxygen. Related to this ability, V2O5 catalyses several useful aerobic oxidation reactions, the largest scale of which underpins the production of sulfuric acid from sulfur dioxide. Sulfuric (or sulphuric acid, H 2 S[[oxygen O]]4 is a strong Mineral acid. It is a poisonous orange solid which, because of its high oxidation state, is both an amphoteric oxide and an oxidising agent. In the context of Biology, poisons are substances that can cause damage, Illness, or Death to Organisms usually by In Chemistry, the oxidation state is an indicator of the degree of Oxidation of an Atom in a Chemical compound. Redox (shorthand for reduction-oxidation reaction describes all Chemical reactions in which atoms have their Oxidation number ( Oxidation state Unlike most metal oxides, it dissolves slightly in water due to hydrolysis. Solubility is the characteristic Physical property referring to the ability of a given substance the Solute, to dissolve in a Solvent.
Vanadium(V) indicates that vanadium is in the +5 oxidation state. Vanadium (vəˈneɪdiəm is a Chemical element that has the symbol V and Atomic number 23 In Chemistry, the oxidation state is an indicator of the degree of Oxidation of an Atom in a Chemical compound. The oxygen atoms in the compound are in the -2 oxidation state. Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the History See also Atomic theory, Atomism The concept that matter is composed of discrete units and cannot be divided into arbitrarily tiny
Contents |
Chemical properties
Acid-base reactions
V2O5 is an amphoteric oxide. Thus it reacts with strong non-reducing acids to form solutions containing the pale yellow salts containing dioxovanadium(V) centers:
- V2O5 + 2 HNO3 → 2 "VO2(NO3)" + H2O
It also reacts with strong alkali to form polyoxovanadates, which have a complex structure that depends on pH. Nitric acid ( H[[nitrate NO3]] also known as Aqua fortis and spirit of nitre, is a highly corrosive and In Chemistry, an alkali (from Arabic: Al-Qaly القلي القالي) is a basic, ionic salt of an Alkali metal pH is the measure of the acidity or alkalinity of a Solution. [1] If excess aqueous sodium hydroxide is used, the product is a colourless salt, sodium orthovanadate, Na3VO4. Sodium hydroxide ( Na[[hydroxide OH]]) also known as Lye, caustic soda and (incorrectly according to IUPAC nomenclature Salt is a Dietary mineral composed primarily of Sodium chloride that is essential for Animal life but toxic to most land plants Sodium orthovanadate is the chemical compound Na3VO4 and contains the tetrahedral VO43− If acid is slowly added to a solution of Na3VO4, the colour gradually deepens through orange to red before brown hydrated V2O5 precipitates around pH 2. These solutions contain mainly the ions HVO42− and V2O74− between pH 9 and 13, but below pH 9 more exotic species such as V4O124− and HV10O285− predominate.
Thionyl chloride converts it to VOCl3:
Redox reactions
V2O5 is easily reduced in acidic media to the stable vanadium(IV) species, the blue vanadyl ion (VO(H2O)52+). Thionyl chloride (or thionyl dichloride) is an Inorganic compound with the formula S[[Oxygen O]] Cl 2 Vanadium oxytrichloride is the Inorganic compound with the formula VOCl3 A solid' object is in the States of matter characterized by resistance to Deformation and changes of Volume. Thionyl chloride (or thionyl dichloride) is an Inorganic compound with the formula S[[Oxygen O]] Cl 2 Liquid is one of the principal States of matter. A liquid is a Fluid that has the particles loose and can freely form a distinct surface at the boundaries of This page is about the physical properties of gas as a state of matter The vanadyl or oxovanadium(IV cation, 2+ is a blue-coloured Vanadium oxocation. This conversion illustrates the redox properties of V2O5. Redox (shorthand for reduction-oxidation reaction describes all Chemical reactions in which atoms have their Oxidation number ( Oxidation state For example, hydrochloric acid and hydrobromic acid are oxidised to the corresponding halogen, e. Hydrochloric acid is the Solution of Hydrogen chloride ( H[[Chlorine Cl]] in water Hydrobromic Acid is formed by dissolving the diatomic molecule Hydrogen bromide in water Abundance Owing to their high Reactivity, the halogens are found in the environment only in compounds or as Ions Halide ions and oxoanions g. ,
Solid V2O5 is reduced by oxalic acid, CO, and SO2 to give vanadium(IV) oxide, VO2 as a deep-blue solid. A solid' object is in the States of matter characterized by resistance to Deformation and changes of Volume. The chloride Ion is formed when the element Chlorine picks up one Electron to form an Anion (negatively-charged ion Cl&minus Chlorine (ˈklɔriːn from the Greek word 'χλωρóς' ( khlôros, meaning 'pale green' is the Chemical element with Atomic number 17 and Oxalic acid is the Chemical compound with the formula H2C2O4 This Dicarboxylic acid is better described with the Carbon monoxide, with the chemical formula CO is a colorless odorless tasteless yet highly toxic Gas. Vanadium(IV oxide is the chemical compound VO2 It is formed in the contact process from V2O5 which acts as a Catalyst. Further reduction using hydrogen or excess CO can lead to complex mixtures of oxides such as V4O7 and V5O9 before black V2O3 is reached. Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 Vanadates or vanadyl(V) compounds in acid solution are reduced by zinc amalgam through the interestingly colorful pathway -
colorless "VO3−" → yellow "VO2+" → blue "VO2+" → green "V3+" → purple "V2+" The ions are of course hydrated to varying degrees.
Preparation
Technical grade V2O5 is produced as a black powder used for the production of vanadium metal and ferrovanadium. Vanadium (vəˈneɪdiəm is a Chemical element that has the symbol V and Atomic number 23 Ferroalloy refers to various Alloys of Iron with a high proportion of one or more other element, Manganese or Silicon for example [1] A vanadium ore or vanadium-rich residue is treated with sodium carbonate to produce sodium metavanadate, NaVO3. Sodium carbonate (also known as washing soda or soda ash), is a Sodium Salt of Carbonic acid. Sodium metavanadate is a yellow solid which is soluble in water This material is then acidified to pH 2-3 using H2SO4 to yield a precipitate of "red cake" (see above). Sulfuric (or sulphuric acid, H 2 S[[oxygen O]]4 is a strong Mineral acid. The red cake is then melted at 690 °C to produce the crude V2O5.
Vanadium(V) oxide is also the main product when vanadium metal is heated with excess oxygen, but this product is contaminated with other lower oxides. Vanadium (vəˈneɪdiəm is a Chemical element that has the symbol V and Atomic number 23 Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the A more satisfactory laboratory preparation involves the decomposition of ammonium metavanadate at around 200 °C:
Uses
Sulfuric acid production
The most important use of vanadium(V) oxide is in the manufacture of sulfuric acid, an important industrial chemical with an annual production of 145 million tonnes in 1986. Ammonium metavanadate, NH4VO3 a yellow crystalline solid which dissolves in water is the most common laboratory vanadate reagent along with potassium A solid' object is in the States of matter characterized by resistance to Deformation and changes of Volume. Ammonia is a compound with the formula N[[hydrogen H3]] It is normally encountered as a Gas with a characteristic pungent Odor Sulfuric (or sulphuric acid, H 2 S[[oxygen O]]4 is a strong Mineral acid. [1] Vanadium(V) serves the crucial purpose of catalysing the mildly exothermic oxidation of sulfur dioxide to sulfur trioxide by air in the contact process:
- 2 SO2 + O2 ⇌ 2 SO3
The discovery of this simple reaction, for which V2O5 is the most effective catalyst, allowed sulfuric acid to become the cheap commodity chemical it is today. Catalysis is the process in which the rate of a Chemical reaction is increased by means of a Chemical substance known as a catalyst An exothermic reaction is a Chemical reaction that releases Heat. Redox (shorthand for reduction-oxidation reaction describes all Chemical reactions in which atoms have their Oxidation number ( Oxidation state Sulfur trioxide (also spelled sulphur trioxide) is the chemical compound with the formula SO3 The contact process is the current method of producing Sulfuric acid in the high concentrations needed for industrial processes Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the The reaction is performed between 400 and 620 °C; below 400 °C the V2O5 is inactive as a catalyst, and above 620 °C; it begins to break down. The Celsius Temperature scale was previously known as the centigrade scale. Since it is known that V2O5 can be reduced to VO2 by SO2, one likely catalytic cycle is as follows:
- SO2 + V2O5(s) → SO3(g) + 2 VO2(s) followed by
- 2 VO2(s) +1/2 O2(g) → V2O5
Paradoxically, it is also used as catalyst in the selective catalytic reduction of NOx emissions in some power plants. Vanadium(IV oxide is the chemical compound VO2 It is formed in the contact process from V2O5 which acts as a Catalyst. Selective catalytic reduction ( SCR) is a means of converting nitrogen oxides, also referred to as {{chem|NO|x}} with the aid of a Catalyst into The term nitrogen oxide typically refers to any Binary compound of Oxygen and Nitrogen, or to a mixture of such compounds Nitric A power station (also referred to as generating station, power plant or powerhouse) is an industrial facility for the generation of Due to its effectiveness in converting sulfur dioxide into sulfur trioxide, and thereby sulfuric acid, special care must be taken with the operating temperatures and placement of a power plant's SCR unit when firing sulfur-containing fuels.
Other oxidations
Maleic anhydride is another important industrial material, used for the manufacture of polyester resins and alkyd resins. Maleic anhydride ( cis -butenedioic anhydride toxilic anhydride dihydro-25-dioxofuran is an Organic compound with the formula C4H2O3 Polyester is a category of Polymers which contain the Ester Functional group in their main chain [2] Vanadium(V) oxide can catalyse its production from a variety of organic starting materials such as n-butane, furfural and benzene, the last of which is the usual commercial method. Butane, also called n -butane, is the unbranched Alkane with four Carbon Atoms CH3CH2CH2CH3 The Chemical compound furfural is an industrial chemical derived from a variety of agricultural byproducts including corncobs, Oat and Benzene, or benzol, is an organic Chemical compound and a known Carcinogen with the molecular formula C 6 H 6 In a related process, phthalic anhydride, used for making plasticisers for PVC manufacture, may be produced by V2O5 catalysed oxidation of ortho-xylene or naphthalene at 350-400°C. Phthalic anhydride is the Organic compound with the formula C6H4(CO2O Plasticizers are additives that increase the Plasticity or Fluidity of the material to which they are added these include plastics cement concrete wallboard and o-Xylene|m-Xylene|p-XyleneThe term xylene or xylol refers to a mixture of three Benzene derivatives which is used as a Solvent in the Printing Naphthalene, also known as naphthalin, naphthaline, tar camphor, white tar, albocarbon, or antimite and not to be
Other applications
In terms of quantity, the major use for vanadium(V) oxide is in the production of ferrovanadium (see above). Ferroalloy refers to various Alloys of Iron with a high proportion of one or more other element, Manganese or Silicon for example The oxide is heated with scrap iron and aluminium, producing the iron-vanadium alloy along with alumina as a by-product. Iron (ˈаɪɚn is a Chemical element with the symbol Fe (ferrum and Atomic number 26 WikipediaNaming In 2005 a shortage of V2O5 caused a price rise to around $40/kg, which in turn caused a rise in the price of ferrovanadium.
Due to its high thermal coefficient of resistance, vanadium(V) oxide finds use as a detector material in bolometers and microbolometer arrays for thermal imaging. A bolometer is a device for measuring the energy of incident Electromagnetic radiation. A microbolometer is a specific type of Bolometer used as a detector in a Thermal camera. wiki stranglesnakejpg|thumb|Thermographic image of a Snake held by a human]] Infrared Thermography, thermal imaging, or thermal video, is a type of
Possible new uses include the preparation of bismuth vanadate ceramics for use in solid oxide fuel cells. A fuel cell is an electrochemical conversion device It produces electricity from Fuel (on the Anode side and an oxidant (on the [3]
Biological activity
Despite being highly toxic in humans, vanadium occurs in some organisms, notably the Ascidiacea (sea squirts). Vanadium (vəˈneɪdiəm is a Chemical element that has the symbol V and Atomic number 23 Ascidiacea (commonly known as the ascidians or Sea squirts is a class in the Tunicata Subphylum of sac-like marine Filter feeders These organisms contain the protein vanabins, the role of which is unclear. Vanabins (also known as vanadium-associated proteins or vanadium chromagen) are a specific group of Vanadium -binding Metalloproteins Found Vanadate (VO43−), formed when V2O5 by hydrolysis of V2O5 at high pH, appears to inhibit enzymes that process phosphate (PO43−). However the exact mode of action remains elusive. [1]
References
- ^ a b c d N. N. Greenwood, A. Earnshaw, Chemistry of the Elements, 2nd ed. , Butterworth-Heinemann, Oxford, UK, 1997.
- ^ Basic Organic Chemistry: Part 5, Industrial Products, J. M. Tedder, A. Nechvatal, A. H. Tubb (editors), John Wiley & Sons, Chichester, UK (1975).
- ^ B. Vaidhyanathan, K. Balaji, K. J. Rao (1998). "Microwave-Assisted Solid-State Synthesis of Oxide Ion Conducting Stabilized Bismuth Vanadate Phases". Chem. Mater. 10: 3400. Chemistry of Materials (abbreviated Chem Mater) is a Scientific journal published by the American Chemical Society. doi:. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.
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