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Germanium(IV) Bromide
Germanium tetrabromide is an inorganic compound with the formula GeBr4. It can be formed by reacting solid germanium and gaseous bromine. :Ge + 2Br2 -> GeBr4 From this reaction, GeBr4 has a heat of formation of 83.3 kcal/mol. The compound is liquid at 25 °C, and forms an interlocking liquid structure. From room temperature down to −60 °C the structure takes on a cubic α form, whereas at lower temperatures it takes on a monoclinic β form. References Germanium(IV) compounds Bromides {{inorganic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tin(IV) Iodide
Tin(IV) iodide, also known as stannic iodide, is the chemical compound with the formula SnI4. This tetrahedral molecule crystallizes as a bright orange solid that dissolves readily in nonpolar solvents such as benzene. The compound is usually prepared by the reaction of iodine and tin: : Sn + 2 I2 → SnI4 The compound hydrolyses in water. In aqueous hydroiodic acid, it reacts to form a rare example of a hexaiodometallate: : SnI4 + 2 I− → nI6sup>2− See also *Tin(II) iodide *Tin(IV) chloride Tin(IV) chloride, also known as tin tetrachloride or stannic chloride, is an inorganic compound with the formula Sn Cl4. It is a colorless hygroscopic liquid, which fumes on contact with air. It is used as a precursor to other tin compounds. It w ... References {{Iodides Tin(IV) compounds Iodides Metal halides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tin(IV) Bromide
Tin(IV) bromide is the chemical compound SnBr4. It is a colourless low melting solid. SnBr4 can be prepared by reaction of the elements at normal temperatures: :Sn + 2Br2 → SnBr4 In aqueous solution Sn(H2O)64+ is the principal ionic species amongst a range of 6 coordinate ions with from 0-6 bromide ligands (e.g. Sn(H2O)64+, SnBr(H2O)53+); in basic solution the Sn(OH)62− ion is present. SnBr4 forms 1:1 and 1:2 complexes with ligands, e.g. with trimethylphosphine Trimethylphosphine is a neutral organophosphorus compound with the formula P(CH3)3, commonly abbreviated as PMe3. This colorless liquid has a strongly unpleasant odor, characteristic of alkylphosphines. The compound is a common ligand in coordin ... the following can be produced, SnBr4.P(CH3)3 and SnBr4.2P(CH3)3. SnBr4 crystallises in a monoclinic form with molecular SnBr4 units that have distorted tetrahedral geometry, with mean Sn-Br bond lengths of 242.3 pm. References {{DEFAULTSORT:Tin(Iv) Bromide Bro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germanium Tetrafluoride
Germanium tetrafluoride (GeF4) is a chemical compound of germanium and fluorine. It is a colorless gas. Synthesis Germanium tetrafluoride is formed by treating germanium with fluorine: : Ge + 2 F2 → GeF4 Alternatively germanium dioxide combines with hydrofluoric acid Hydrofluoric acid is a Solution (chemistry), solution of hydrogen fluoride (HF) in water. Solutions of HF are colourless, acidic and highly Corrosive substance, corrosive. It is used to make most fluorine-containing compounds; examples include th ... (HF): : GeO2 + 4 HF → GeF4 + 2 H2O It is also formed during the thermal decomposition of a complex salt, Ba eF6 : Ba(GeF6) → GeF4 + BaF2 Properties Germanium tetrafluoride is a noncombustible, strongly fuming gas with a garlic-like odor. It reacts with water to form hydrofluoric acid and germanium dioxide. Decomposition occurs above 1000 °C. Reaction of GeF4 with fluoride sources produces GeF5− anions with octahedral coordination around Ge atom due to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germanium Tetrachloride
Germanium tetrachloride is a colourless, fuming liquid with a peculiar, acidic odour. It is used as an intermediate in the production of purified germanium metal. In recent years, GeCl4 usage has increased substantially due to its use as a reagent for fiber optic production. Production Most commercial production of germanium is from treating flue-dusts of zinc- and copper-ore smelters, although a significant source is also found in the ash from the combustion of certain types of coal called vitrain. Germanium tetrachloride is an intermediate for the purification of germanium metal or its oxide, GeO2."Germanium" Mineral Commodity Profile, U.S. Geological Survey, 2005. Germanium tetrachloride can be generated directly from GeO2 (germanium dioxide) by dissolution of the oxide in concentrated hydrochloric acid. The resulting mixture is fractionally distilled to purify and separate the germanium tetrachloride from other products and impurities."The Elements" C. R. Hammond, David R. Lide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germanium Tetraiodide
Germanium iodide is a chemical compound of germanium and iodine. Two such compounds exist: germanium(II) iodide, , and germanium(IV) iodide . Germanium(II) iodide is an orange-yellow crystalline solid which decomposes on melting. Its specific density is 5.37 and it can be sublimed at 240 °C in a vacuum. It can be prepared by reducing germanium(IV) iodide with aqueous hypophosphorous acid in the presence of hydroiodic acid. It is oxidised by a solution of potassium iodide in hydrochloric acid to germanium(IV) iodide. It reacts with acetylene at 140 °C to form an analogue of cyclohexa-1,4-diene in which the methylene groups, , are replaced with diiodogermylene groups, . Germanium(IV) iodide is an orange-red crystalline solid with melting point 144 °C and boiling point The boiling point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid and the liquid changes into a vapor. The boiling point of a liq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Tetrabromide
Tetrabromomethane, CBr4, also known as carbon tetrabromide, is a carbon bromide. Both names are acceptable under IUPAC nomenclature. Physical properties Tetrabromomethane has two polymorphs: crystalline II or β below 46.9 °C (320.0 K) and crystalline I or α above 46.9 °C. Monoclinic polymorph has space group ''C2/c'' with lattice constants: ''a'' = 20.9, ''b'' = 12.1, ''c'' = 21.2 (.10−1 nm), β = 110.5°.F. Brezina, J. Mollin, R. Pastorek, Z. Sindelar. ''Chemicke tabulky anorganickych sloucenin'' (''Chemical tables of inorganic compounds''). SNTL, 1986. Bond energy of C-Br is 235 kJ.mol−1.N. N. Greenwood, A. Earnshaw. ''Chemie prvku'' (''Chemistry of the Elements''). Informatorium, Prague, 1993. Due to its symmetrically substituted tetrahedral structure, its dipole moment is 0 Debye. Critical temperature is 439 °C (712 K) and critical pressure is 4.26 MPa. Plastic crystallinity The high temperature α phase is known as a plastic crystal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silicon Tetrabromide
Silicon tetrabromide, also known as tetrabromosilane, is the inorganic compound with the formula SiBr4. This colorless liquid has a suffocating odor due to its tendency to hydrolyze with release of hydrogen bromide.''Encyclopedia of Inorganic Chemistry;'' King, B. R.; John Wiley & Sons Ltd.: New York, NY, 1994; Vol 7, pp 3779–3782. The general properties of silicon tetrabromide closely resemble those of the more commonly used silicon tetrachloride. Comparison of SiX4 The properties of the tetrasilanes, all of which are tetrahedral, are significantly affected by nature of the halide. These trends apply also to the mixed halides. Melting points, boiling points, and bond lengths increase with the atomic mass of the halide. The opposite trend is observed for the Si-X bond energies. Lewis acidity Covalently saturated silicon complexes like SiBr4, along with tetrahalides of germanium (Ge) and tin (Sn), are Lewis acids.Davydova, E. I.; Timoshkin, A. Y.; Sevastianova, T. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germanium
Germanium is a chemical element with the symbol Ge and atomic number 32. It is lustrous, hard-brittle, grayish-white and similar in appearance to silicon. It is a metalloid in the carbon group that is chemically similar to its group neighbors silicon and tin. Like silicon, germanium naturally reacts and forms complexes with oxygen in nature. Because it seldom appears in high concentration, germanium was discovered comparatively late in the discovery of the elements. Germanium ranks near fiftieth in relative abundance of the elements in the Earth's crust. In 1869, Dmitri Mendeleev predicted its existence and some of its properties from its position on his periodic table, and called the element ekasilicon. In 1886, Clemens Winkler at Freiberg University found the new element, along with silver and sulfur, in the mineral argyrodite. Winkler named the element after his country, Germany. Germanium is mined primarily from sphalerite (the primary ore of zinc), though germanium is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bromine
Bromine is a chemical element with the symbol Br and atomic number 35. It is the third-lightest element in group 17 of the periodic table (halogens) and is a volatile red-brown liquid at room temperature that evaporates readily to form a similarly coloured vapour. Its properties are intermediate between those of chlorine and iodine. Isolated independently by two chemists, Carl Jacob Löwig (in 1825) and Antoine Jérôme Balard (in 1826), its name was derived from the Ancient Greek (bromos) meaning "stench", referring to its sharp and pungent smell. Elemental bromine is very reactive and thus does not occur as a native element in nature but it occurs in colourless soluble crystalline mineral halide salts, analogous to table salt. In fact, bromine and all the halogens are so reactive that they form bonds in pairs—never in single atoms. While it is rather rare in the Earth's crust, the high solubility of the bromide ion (Br) has caused its accumulation in the oceans. Commercial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heat Of Formation
In chemistry and thermodynamics, the standard enthalpy of formation or standard heat of formation of a compound is the change of enthalpy during the formation of 1 mole of the substance from its constituent elements in their reference state, with all substances in their standard states. The standard pressure value is recommended by IUPAC, although prior to 1982 the value 1.00 atm (101.325 kPa) was used. There is no standard temperature. Its symbol is . The superscript Plimsoll on this symbol indicates that the process has occurred under standard conditions at the specified temperature (usually 25 °C or 298.15 K). Standard states are as follows: # For a gas: the hypothetical state it would have assuming it obeyed the ideal gas equation at a pressure of 1 bar # For a gaseous or solid solute present in a diluted ideal solution: the hypothetical state of concentration of the solute of exactly one mole per liter (1 M) at a pressure of 1 bar extrapolated from i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germanium(IV) Compounds
Germanium is a chemical element with the symbol Ge and atomic number 32. It is lustrous, hard-brittle, grayish-white and similar in appearance to silicon. It is a metalloid in the carbon group that is chemically similar to its group neighbors silicon and tin. Like silicon, germanium naturally reacts and forms complexes with oxygen in nature. Because it seldom appears in high concentration, germanium was discovered comparatively late in the discovery of the elements. Germanium ranks near fiftieth in relative abundance of the elements in the Earth's crust. In 1869, Dmitri Mendeleev predicted its existence and some of its properties from its position on his periodic table, and called the element ekasilicon. In 1886, Clemens Winkler at Freiberg University found the new element, along with silver and sulfur, in the mineral argyrodite. Winkler named the element after his country, Germany. Germanium is mined primarily from sphalerite (the primary ore of zinc), though germanium is al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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