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Disulfur Difluoride
Disulfur difluoride is a halide of sulfur, with the chemical formula S2F2. Structure Disulfur difluoride will undergo intramolecular rearrangement in the presence of alkali elements' fluorides, yielding the isomer S=SF2: ::FS-SF -> \atop \ce\underset Synthesis Silver(II) fluoride can fluorinate sulfur in a strictly dry container, and the reaction produces FS-SF: :: + \underset -> \atop \ce + 8 AgF S=SF2 can be synthesized with the reaction of potassium fluorosulfite and disulfur dichloride: ::2 KSO2F + S2Cl2 -> S=SF2 + 2KCl + 2 SO2 Reactions * Decomposing to sulfur tetrafluoride and sulfur when heated: ::2S2F2 -> \atop \ce \underset + 3S * Treated with water: ::2S2F2 + 2H2O -> SO2 + 3S + 4HF * Reacting with sulfuric acid: :: + \underset -> \atop \ce + + 2H2O * Reacting with sodium hydroxide: ::2S2F2 + 6NaOH -> Na2SO3 + 3S + 4NaF + 3H2O * Reacting with oxygen at high pressure, using nitrogen dioxide as the catalyst: :: + 5O2 -> \atop \overset\ce + 3SO3 * Cond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dioxygen Difluoride
Dioxygen difluoride is a compound of fluorine and oxygen with the molecular formula O2F2. It can exist as an orange-colored solid which melts into a red liquid at . It is an extremely strong oxidant and decomposes into oxygen and fluorine even at at a rate of 4% per its lifetime at room temperature is thus extremely short. Dioxygen difluoride reacts vigorously with nearly every chemical it encounters (including ordinary ice) leading to its onomatopoeic nickname "FOOF" (a play on its chemical structure and its explosive tendencies). Preparation Dioxygen difluoride can be obtained by subjecting a 1:1 mixture of gaseous fluorine and oxygen at low pressure (7–17 mmHg (0.9–2.3 kPa) is optimal) to an electric discharge of 25–30 mA at 2.1–2.4 kV. A similar method was used for the first synthesis by Otto Ruff in 1933. Another synthesis involves mixing and in a stainless steel vessel cooled to , followed by exposing the elements to bremsstrahlung fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfuric Acid
Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid ( 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 viscous liquid that is miscible with water. Pure sulfuric acid does not exist naturally on Earth due to its strong affinity to water vapor; it is hygroscopic and readily absorbs water vapor from the air. Concentrated sulfuric acid is highly corrosive towards other materials, from rocks to metals, since it is an oxidant with powerful dehydrating properties. 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 released; thus the reverse procedure of adding water to the acid should not be performed since the heat released may boi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disulfides
In biochemistry, a disulfide (or disulphide in British English) refers to a functional group with the structure . The linkage is also called an SS-bond or sometimes a disulfide bridge and is usually derived by the coupling of two thiol groups. In biology, disulfide bridges formed between thiol groups in two cysteine residues are an important component of the secondary and tertiary structure of proteins. ''Persulfide'' usually refers to compounds. In inorganic chemistry disulfide usually refers to the corresponding anion (−S−S−). Organic disulfides Symmetrical disulfides are compounds of the formula . Most disulfides encountered in organo sulfur chemistry are symmetrical disulfides. Unsymmetrical disulfides (also called heterodisulfides) are compounds of the formula . They are less common in organic chemistry, but most disulfides in nature are unsymmetrical. Properties The disulfide bonds are strong, with a typical bond dissociation energy of 60 kcal/mol (251&nbs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,3-Difluoro-trisulfane-1,1-difluoride
1,3-Difluoro-trisulfane-1,1-difluoride is an inorganic molecular substance with the structure SF3SSF, consisting of sulfur in a low oxidation state with fluorine. The compound consists of a chain of three sulfur atoms, with three fluorine atoms bonded to the sulfur on one end and the fourth fluorine bonded to the sulfur on the other end. It has a melting point of -62 °C and a boiling point of 94 °C. As a gas, it is unstable and breaks up to form SSF2 and SF4. SF3SSF is produced by the condensation of sulfur difluoride Sulfur difluoride is an inorganic compound with the chemical formula SF2. It can be generated by the reaction of sulfur dichloride and potassium fluoride or mercury(II) fluoride at low pressures: :SCl2 + 2 KF → SF2 + 2 KCl :SCl2 + HgF2 → SF2 + ... and an isomer of SSF2. The reaction S3F4 SSF2 + SF2 uses 6 kJ/mol. Possible isomers of its S3F4 molecular formula include FSSF2SF, which has a spontaneous fluorine migration to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfur Difluoride
Sulfur difluoride is an inorganic compound with the chemical formula SF2. It can be generated by the reaction of sulfur dichloride and potassium fluoride or mercury(II) fluoride at low pressures: :SCl2 + 2 KF → SF2 + 2 KCl :SCl2 + HgF2 → SF2 + HgCl2 The F−S−F bond angle is 98°, and the length of S−F bond is 159 pm. The compound is highly unstable, decomposing to FSSF3. This unsymmetrical isomer of S2F4 is proposed to arise via insertion of SF2 into the S−F bond of a second molecule SF2: It can also be formed from oxygen difluoride and hydrogen sulfide Hydrogen sulfide is a chemical compound with the formula . It is a colorless chalcogen-hydride gas, and is poisonous, corrosive, and flammable, with trace amounts in ambient atmosphere having a characteristic foul odor of rotten eggs. The unde ...: :OF2 + H2S → SF2 + H2O References {{Fluorides Sulfur(II) compounds Fluorides Sulfur fluorides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalyst
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant, or heterogeneous, whose components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category. Catalysis is ubiquitous in chemical industry of all kinds. Estimates are that 90% of all commercially produced chemical products involve catalysts at some s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogen Dioxide
Nitrogen dioxide is a chemical compound with the formula . It is one of several nitrogen oxides. is an intermediate in the industrial synthesis of nitric acid, millions of tons of which are produced each year for use primarily in the production of fertilizers. At higher temperatures it is a reddish-brown gas. It can be fatal if inhaled in large quantities. Nitrogen dioxide is a paramagnetic, bent molecule with C2v point group symmetry. It is included in the NOx family of atmospheric pollutants. Properties Nitrogen dioxide is a reddish-brown gas with a pungent, acrid odor above , becomes a yellowish-brown liquid below , and converts to the colorless dinitrogen tetroxide () below . The bond length between the nitrogen atom and the oxygen atom is 119.7 pm. This bond length is consistent with a bond order between one and two. Unlike ozone, O3, the ground electronic state of nitrogen dioxide is a doublet state, since nitrogen has one unpaired electron, which decreases ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Hydroxide
Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly caustic base and alkali that decomposes proteins at ordinary ambient temperatures and may cause severe chemical burns. It is highly soluble in water, and readily absorbs moisture and carbon dioxide from the air. It forms a series of hydrates . The monohydrate crystallizes from water solutions between 12.3 and 61.8 °C. The commercially available "sodium hydroxide" is often this monohydrate, and published data may refer to it instead of the anhydrous compound. As one of the simplest hydroxides, sodium hydroxide is frequently used alongside neutral water and acidic hydrochloric acid to demonstrate the pH scale to chemistry students. Sodium hydroxide is used in many industries: in the manufacture of pulp and paper, textiles, drinking water, soaps and deterge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfur Tetrafluoride
Sulfur tetrafluoride is the chemical compound with the formula S F4. It is a colorless corrosive gas that releases dangerous HF upon exposure to water or moisture. Despite these unwelcome characteristics, this compound is a useful reagent for the preparation of organofluorine compounds, some of which are important in the pharmaceutical and specialty chemical industries. Structure Sulfur in SF4 is in the formal +4 oxidation state. Of sulfur's total of six valence electrons, two form a lone pair. The structure of SF4 can therefore be anticipated using the principles of VSEPR theory: it is a see-saw shape, with S at the center. One of the three equatorial positions is occupied by a nonbonding lone pair of electrons. Consequently, the molecule has two distinct types of F ligands, two axial and two equatorial. The relevant bond distances are = 164.3 pm and = 154.2 pm. It is typical for the axial ligands in hypervalent molecules to be bonded less strongly. In c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disulfur Dichloride
Disulfur dichloride is the inorganic compound of sulfur and chlorine with the Chemical formula, formula S2Cl2. Some alternative names for this compound are ''sulfur monochloride'' (the name implied by its empirical formula, SCl), ''disulphur dichloride'' (British English Spelling) and ''sulphur monochloride'' (British English Spelling). S2Cl2 has the structure implied by the formula Cl−S−S−Cl, wherein the angle between the Cla−S−S and S−S−Clb planes is 90°. This structure is referred to as ''gauche'', and is akin to that for Hydrogen peroxide, H2O2. A rare isomer of S2Cl2 is S=SCl2; this isomer forms transiently when S2Cl2 is exposed to UV-radiation (see thiosulfoxides). Synthesis, basic properties, reactions Pure disulfur dichloride is a yellow liquid that "smokes" in moist air due to reaction with water. An idealized (but complicated) equation is: :16 S2Cl2 + 16 H2O → 8 SO2 + 32 HCl + 3 octasulfur, S8 It is produced by partial chlorination of elemental sulfur. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disulfur Dichloride
Disulfur dichloride is the inorganic compound of sulfur and chlorine with the Chemical formula, formula S2Cl2. Some alternative names for this compound are ''sulfur monochloride'' (the name implied by its empirical formula, SCl), ''disulphur dichloride'' (British English Spelling) and ''sulphur monochloride'' (British English Spelling). S2Cl2 has the structure implied by the formula Cl−S−S−Cl, wherein the angle between the Cla−S−S and S−S−Clb planes is 90°. This structure is referred to as ''gauche'', and is akin to that for Hydrogen peroxide, H2O2. A rare isomer of S2Cl2 is S=SCl2; this isomer forms transiently when S2Cl2 is exposed to UV-radiation (see thiosulfoxides). Synthesis, basic properties, reactions Pure disulfur dichloride is a yellow liquid that "smokes" in moist air due to reaction with water. An idealized (but complicated) equation is: :16 S2Cl2 + 16 H2O → 8 SO2 + 32 HCl + 3 octasulfur, S8 It is produced by partial chlorination of elemental sulfur. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Fluorosulfite
Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It was first isolated from potash, the ashes of plants, from which its name derives. In the periodic table, potassium is one of the alkali metals, all of which have a single valence electron in the outer electron shell, that is easily removed to create an ion with a positive charge – a cation, that combines with anions to form salts. Potassium in nature occurs only in ionic salts. Elemental potassium reacts vigorously with water, generating sufficient heat to ignite hydrogen emitted in the reaction, and burning with a lilac- colored flame. It is found dissolved in sea water (which is 0.04% potassium by weight), and occurs in many minerals such as orthoclase, a c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
