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Diiodine Tetroxide
Diiodine tetraoxide, I2O4, is a chemical compound of oxygen and iodine. It belongs to the class of iodine oxides, and is a mixed oxide, consisting of iodine(III) and iodine(V) oxidation states. Synthesis The oxide is formed by the reaction of hot concentrated sulfuric acid on iodic acid for several days. : It is formed from diiodine pentoxide and iodine in concentrated sulfuric acid or iodosyl sulfate (IO)2SO4 added to water: : Alternatively, excess of concentrated nitric acid oxidizes dry iodine to this salt. Physical properties Diiodine tetraoxide is a yellow, granular powder. At temperatures above 85 °C it decomposes to diiodine pentoxide and iodine: : This process is even faster at 135 °C. It dissolves in hot water to form iodate and iodide. Structurally, the compound is an iodyl iodite O2I-OIO (iodine(V,III) oxide) with bent IVO2 units (I–O distances 1.80 and 1.85 Å; ∠OIO angle 97°) and bent IIIIO2 units (IO distances 1.93 Å, OIO angle 95.8°). Both units are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), nonmetal, and a potent oxidizing agent that readily forms oxides with most elements as well as with other chemical compound, compounds. Oxygen is abundance of elements in Earth's crust, the most abundant element in Earth's crust, making up almost half of the Earth's crust in the form of various oxides such as water, carbon dioxide, iron oxides and silicates.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. It is abundance of chemical elements, the third-most abundant element in the universe after hydrogen and helium. At standard temperature and pressure, two oxygen atoms will chemical bond, bind covalent bond, covalently to form dioxygen, a colorless and odorless diatomic gas with the chemical formula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodine
Iodine is a chemical element; it has symbol I and atomic number 53. The heaviest of the stable halogens, it exists at standard conditions as a semi-lustrous, non-metallic solid that melts to form a deep violet liquid at , and boils to a violet gas at . The element was discovered by the French chemist Bernard Courtois in 1811 and was named two years later by Joseph Louis Gay-Lussac, after the Ancient Greek , meaning 'violet'. Iodine occurs in many oxidation states, including iodide (I−), iodate (), and the various periodate anions. As the heaviest essential mineral nutrient, iodine is required for the synthesis of thyroid hormones. Iodine deficiency affects about two billion people and is the leading preventable cause of intellectual disabilities. The dominant producers of iodine today are Chile and Japan. Due to its high atomic number and ease of attachment to organic compounds, it has also found favour as a non-toxic radiocontrast material. Because of the spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodine Oxide
Iodine oxides are chemical compounds of oxygen and iodine. Iodine has only two stable oxides which are isolatable in bulk, iodine tetroxide and iodine pentoxide, but a number of other oxides are formed in trace quantities or have been hypothesized to exist. The chemistry of these compounds is complicated with only a few having been well characterized. Many have been detected in the atmosphere and are believed to be particularly important in the marine layer, marine boundary layer. Molecular compounds Diiodine monoxide has largely been the subject of theoretical study, but there is some evidence that it may be prepared in a similar manner to dichlorine monoxide, via a reaction between mercury(II) oxide, HgO and I2. The compound appears to be highly unstable but can react with alkenes to give halogenated products. free radical, Radical iodine oxide (IO), iodine dioxide (IO2), collectively referred to as IO and iodine tetroxide ((I2O4) all possess significant and interconnected a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mixed Oxide
In chemistry, a mixed oxide is a somewhat informal name for an oxide that contains cations of more than one chemical element or cations of a single element in several states of oxidation.Advanced Inorganic Chemistry, F. A. Cotton, G. Wilkinson, Interscience, 2d Edition, 1966 The term is usually applied to solid ionic compounds that contain the oxide anion and two or more element cations. Typical examples are ilmenite (), a mixed oxide of iron () and titanium () cations, perovskite and garnet.The cations may be the same element in different ionization states: a notable example is magnetite , which is also known as ferrosoferric oxide , contains the cations ("ferrous" iron) and ("ferric" iron) in 1:2 ratio. Other notable examples include red lead , the ferrites,Alex Goldman (1990), ''Modern ferrite technology'' and the yttrium aluminum garnet ,K. Byrappa, Masahiro Yoshimura (2001), ''Handbook of hydrothermal technology''. William Andrew. 870 pages. used in lasers. The te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidation State
In chemistry, the oxidation state, or oxidation number, is the hypothetical Electrical charge, charge of an atom if all of its Chemical bond, bonds to other atoms are fully Ionic bond, ionic. It describes the degree of oxidation (loss of electrons) of an atom in a chemical compound. Conceptually, the oxidation state may be positive, negative or zero. Beside nearly-pure ionic bonding, many covalent bonds exhibit a strong ionicity, making oxidation state a useful predictor of charge. The oxidation state of an atom does not represent the "real" charge on that atom, or any other actual atomic property. This is particularly true of high oxidation states, where the ionization energy required to produce a multiply positive ion is far greater than the energies available in chemical reactions. Additionally, the oxidation states of atoms in a given compound may vary depending on Electronegativities of the elements (data page), the choice of electronegativity scale used in their calculation. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfuric Acid
Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (English in the Commonwealth of Nations, Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen, and hydrogen, with the molecular formula . It is a colorless, odorless, and Viscosity, viscous liquid that is Miscibility, miscible with water. Pure sulfuric acid does not occur naturally due to its Dehydration reaction, strong affinity to water vapor; it is Hygroscopy, hygroscopic and readily absorbs water vapor from the Atmosphere of Earth, air. Concentrated sulfuric acid is a strong oxidant with powerful dehydrating properties, making it highly corrosive towards other materials, from rocks to metals. Phosphorus pentoxide is a notable exception in that it is not dehydrated by sulfuric acid but, to the contrary, dehydrates sulfuric acid to sulfur trioxide. Upon addition of sulfuric acid to water, a considerable amount of heat is releas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diiodosyl Sulfate
Diiodosyl sulfate is an inorganic compound, a basic salt of iodine and sulfuric acid with the formula (IO)2SO4. It forms yellow crystals. Synthesis Reaction of iodic and sulfuric acids : :2 HIO3 + H2SO4 → (IO)2SO4 + O2 + 2 H2O Passing ozonized oxygen through a solution of iodine in sulfuric acid: :I2 + 3 O3 + H2SO4 → (IO)2SO4 + 3 O2 + H2O Physical properties Diiodosyl sulfate forms yellow hygroscopic crystals and is poorly soluble in cold water. It dissolves in and can be recrystallized from concentrated sulfuric acid. Chemical properties Under the influence of atmospheric moisture, diiodosyl sulfate hydrolyzes with the release of iodine, iodic and sulfuric acids. It decomposes when heated: :4(IO) 2 SO 4 → 2I2O5 + 2I2 + 4SO3 + O2 It reacts with sulfur trioxide Sulfur trioxide (alternative spelling sulphur trioxide) is the chemical compound with the formula SO3. It has been described as "unquestionably the most conomicallyimportant sulfur oxide". It is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diiodine Pentoxide
Iodine pentoxide is the chemical compound with the formula I2O5. This iodine oxide is the anhydride of iodic acid, and one of the few iodine oxides that is stable. It is produced by dehydrating iodic acid at 200 °C in a stream of dry air: :2HIO3 → I2O5 + H2O Structure I2O5 is bent with an I–O–I angle of 139.2°, but the molecule has no mirror plane so its symmetry is C2 rather than C2v. The terminal I–O distances are around 1.80 Å and the bridging I–O distances are around 1.95 Å. Reactions Iodine pentoxide easily oxidises carbon monoxide to carbon dioxide at room temperature: :5 CO + I2O5 → I2 + 5 CO2 This reaction can be used to analyze the concentration of CO in a gaseous sample. I2O5 forms iodyl salts, O2+ with SO3 and S2O6F2, but iodosyl salts, O+ with concentrated sulfuric acid Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (English in the Commonwealth of Nations, Commonwealth spel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodate
An iodate is the polyatomic anion with the formula . It is the most common form of iodine in nature, as it comprises the major iodine-containing ores. Iodate salts are often colorless. They are the salts of iodic acid. Structure Iodate is pyramidal in structure. The O–I–O angles range from 97° to 105°, somewhat smaller than the O–Cl–O angles in chlorate. Reactions Redox Iodate is one of several oxyanions of iodine, and has an oxidation number of +5. It participates in several redox reactions, such as the iodine clock reaction. Iodate shows no tendency to disproportionate to periodate and iodide, in contrast to the situation for chlorate. Iodate is reduced by sulfite: : Iodate oxidizes iodide in acidic conditions: : Similarly, chlorate oxidizes iodide to iodate: : Iodate is also obtained by reducing a periodate with a sulfide. The byproduct of the reaction is a sulfoxide. Acid-base Iodate is unusual in that it forms a strong hydrogen bond with its parent ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodide
An iodide ion is I−. Compounds with iodine in formal oxidation state −1 are called iodides. In everyday life, iodide is most commonly encountered as a component of iodized salt, which many governments mandate. Worldwide, iodine deficiency affects two billion people and is the leading preventable cause of intellectual disability. Structure and characteristics of inorganic iodides Iodide is one of the largest monatomic anions. It is assigned a radius of around 206 picometers. For comparison, the lighter halides are considerably smaller: bromide (196 pm), chloride (181 pm), and fluoride (133 pm). In part because of its size, iodide forms relatively weak bonds with most elements. Most iodide salts are soluble in water, but often less so than the related chlorides and bromides. Iodide, being large, is less hydrophilic compared to the smaller anions. One consequence of this is that sodium iodide is highly soluble in acetone, whereas sodium chloride is not. The l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoclinic
In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three Vector (geometric), vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic system. They form a parallelogram prism (geometry), prism. Hence two pairs of vectors are perpendicular (meet at right angles), while the third pair makes an angle other than 90°. Bravais lattices Two monoclinic Bravais lattices exist: the primitive monoclinic and the base-centered monoclinic. For the base-centered monoclinic lattice, the primitive cell has the shape of an oblique rhombic prism;See , row mC, column Primitive, where the cell parameters are given as a1 = a2, α = β it can be constructed because the two-dimensional centered rectangular base layer can also be described with primitive rhombic axes. The length a of the primitive cell below equals \frac \sqrt of the conventional cell above. Crystal class ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Group
In mathematics, physics and chemistry, a space group is the symmetry group of a repeating pattern in space, usually in three dimensions. The elements of a space group (its symmetry operations) are the rigid transformations of the pattern that leave it unchanged. In three dimensions, space groups are classified into 219 distinct types, or 230 types if chiral copies are considered distinct. Space groups are discrete cocompact groups of isometries of an oriented Euclidean space in any number of dimensions. In dimensions other than 3, they are sometimes called Bieberbach groups. In crystallography, space groups are also called the crystallographic or Fedorov groups, and represent a description of the symmetry of the crystal. A definitive source regarding 3-dimensional space groups is the ''International Tables for Crystallography'' . History Space groups in 2 dimensions are the 17 wallpaper groups which have been known for several centuries, though the proof that the list ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
