Sulfuric acid Molecular structure

Keywords Sulfur hydrides Molecular structures Reactivity Spectra Acidities Application... 

Stelling (1928) found an absorption band in formaldehyde and acetone bisulfite addition compounds at 4992.0 A similar to that in sulfonic acids at 4992.2 and differing from that of metal alkyl (4996.0) and dialkyl sulfites (4997.7). He concluded from this that the sulfonic acid structure must be present. Raman spectral examinations of several aldehyde and ketone bisulfites by Caughlan and Tartar (1941) revealed the presence of a carbon-sulfur bond, possibly a carbon-hydroxyl bond, but no carbon doubly bonded to oxygen. This thus aided in discrediting both the tripartite molecule and the sulfurous acid ester structures. Sundman (1949) believes that formation of a stable monomolecular complex of boric acid and glucose bisulfite would be impossible if Schroeter s tripartite molecular structure were correct. His examinations of this complex led him to believe that its structure could be represented only by ... 

On being heated with sulfur trioxide in sulfuric acid 124 5 tetramethylbenzene was converted to a product of molecular formula C10H14O3S m 94% yield Suggest a reasonable structure for this product... 

Treatment of biphenyl (see Section 11 7 to remind yourself of its structure) with a mixture of nitric acid and sulfuric acid gave two principal products both having the molecular formula C12H9NO2 What are these two products ... 

Treatment of the alcohol whose structure is shown here with sulfuric acid gave as the major organic product a tncychc hydrocarbon of molecular formula CigHig Suggest a reasonable struc ture for this hydrocarbon... 

Another boron sulfide, of stoichiometry BS2, can be made by heating B2S3 and sulfur to 300°C under very carefully defined conditions. It is a colourless, moisture-sensitive material with a porphine-like molecular structure, BgSig, as shown in Fig. 6.29b. An alternative route to BgSie involves the reaction of dibromotrithiadiborolane with trithiocarbonic acid in an H2S generator in dilute CS2 solution ... 

The analysis of phosphates and phosphonates is a considerably complex task due to the great variety of possible molecular structures. Phosphorus-containing anionics are nearly always available as mixtures dependent on the kind of synthesis carried out. For analytical separation the total amount of phosphorus in the molecule has to be ascertained. Thus, the organic and inorganic phosphorus is transformed to orthophosphoric acid by oxidation. The fusion of the substance is performed by the addition of 2 ml of concentrated sulfuric acid to — 100 mg of the substance. The black residue is then oxidized by a mixture of nitric acid and perchloric acid. The resulting orthophosphate can be determined at 8000 K by atom emission spectroscopy. The thermally excited phosphorus atoms emit a characteristic line at a wavelength of 178.23 nm. The extensity of the radiation is used for quantitative determination of the phosphorus content. 

A mass spectrometric study was carried out to establish tbe structure of compoimd 69. Its mass spectrum contains tbe molecular ion peak m/z 252 (16.98%) and a base peak (100%) at m/z 210, corresponding to 2-(2-hydroxypbenyl)benzimidazole (70). A tendency towards decreasing the heterocycle size is characteristic of the mass spectrometric behavior of 1,5-benzodiazepin-2-ones [61] and consequently the mass spectra of these compounds contains intense peaks of the corresponding benzimidazoles. It is also known that the mass spectrometric fragmentation of 1,5-benzodiazepines is similar to their thermal or acid decomposition. In fact, refluxing compound 69 in concentrated sulfuric acid yields benzimidazole 70 as the main product. 

A number of lower sulfur oxides have been described. Most of these oxides are derived from cyclic sulfur polymorphs and were usually prepared by oxidation of these molecules by organic peroxo acids. The oxides have the general formula SraO and n may vary from 5 to 10. For n = 7 even the dioxide S702 is known.4 Not all of these phases were characterized by X-ray diffraction, but the molecular structures are certain with respect to vibrational spectroscopy. The oxygen atom is in exo position with respect to the sulfur ring as it has been shown by X-ray diffraction for SgO and S70, respectively (Figure 2).5,6... 

Working first with Polanyi, Weissenberg, and Brill, and later as the leader of the Textile Chemistry Section, Mark successively published papers on the crystal structures of hexamethylenetetramine, pentaerythritol, zinc salts, tin, urea, tin salts, triphenylmethane, bismuth, graphite, sulfur, oxalic acid, acetaldehyde, ammonia, ethane, diborane, carbon dioxide, and some aluminum silicates. Each paper showed his and the laboratory s increasing sophistication in the technique of X-ray diffraction. Their work over the period broadened to include contributions to the theories of atomic and molecular structure and X-ray scattering theory. A number of his papers were particularly notable including his work with Polanyi on the structure of white tin ( 3, 4 ), E. Wigner on the structure of rhombic sulfur (5), and E. Pohland on the low temperature crystal structure of ammonia and carbon dioxide (6, 7). The Mark-Szilard effect, a classical component of X-ray physics, was a result of his collaboration with Leo Szilard (8). And his work with E. A. Hauser (9, 10, 11) on rubber and J. R. 

Alfassi, Z. B S. Padmaja, P. Neta, and R. E. Huie, Rate Constants for Reactions of NO, Radicals with Organic Compounds in Water and Acetonitrile, J. Phys. Chem., 97, 3780-3782 (1993). Allen, H. C., J. M. Laux, R. Vogt, B. J. Finlayson-Pitts, and J. C. Hemminger, Water-Induced Reorganization of Ultrathin Nitrate Films on NaCI—Implications for the Tropospheric Chemistry of Sea Salt Particles, J. Phys. Chem., 100, 6371-6375 (1996). Allen, H. C., D. E. Gragson, and G. L. Richmond, Molecular Structure and Adsorption of Dimethyl Sulfoxide at the Surface of Aqueous Solutions, J. Phys. Chem. B, 103, 660-666 (1999). Anthony, S. E R. T. Tisdale, R. S. Disselkamp, and M. A. Tolbert, FTIR Studies of Low Temperature Sulfuric Acid Aerosols, Geophys. Res. Lett., 22, 1105-1108 (1995). 

Dyes, Dye Intermediates, and Naphthalene. Several thousand different synthetic dyes are known, having a total worldwide consumption of 298 million kg/yr (see Dyes and dye intermediates). Many dyes contain some form of sulfonate as —S03H, —S03Na, or — SC NH. Acid dyes, solvent dyes, basic dyes, disperse dyes, fiber-reactive dyes, and vat dyes can have one or more sulfonic acid groups incorporated into their molecular structure. The raw materials used for the manufacture of dyes are mainly aromatic hydrocarbons (67—74) and include benzene, toluene, naphthalene, anthracene, pyrene, phenol (qv), pyridine, and carbazole. Anthraquinone sulfonic acid is an important dye intermediate and is prepared by sulfonation of anthraquinone using sulfur trioxide and sulfuric acid. 

The first structural report on a phthalocyanine complex concerned [Ni(pc)J (Table 110 I).2878 In the crystal lattice of this compound the square planar macrocycles are arrayed in slipped stacks such that the distance between the molecular planes along the perpendicular direction is 388 pm. [Ni(pc)] may be prepared by a variety of methods 2873,2871 2880 a convenient one is heating a foil of elemental nickel in o-cyanobenzamide at 270 °C (Scheme 60).2881 [Ni(pc)] is insoluble in the most common organic solvents, but soluble in concentrated sulfuric acid from which it is reprecipitated unchanged upon dilution. This complex is thermally very stable and may be sublimed in vacuo. The reduction of [Ni(pc)] can be accomplished by chemical or electrochemical methods and results in ligand-based reduced anions [Ni(pc)]" ( = 1, 2). Analogously, the electrochemical oxidation results in the oxidized ligand. 3... 

Diperoxyketals are solids of colorless liquids and are soluble in common organic solvents and insoluble in water. The physical properties and structures of some diperoxyketals arc listed in Tabic 7. In the pure state, tlie low molecular weight compounds can decompose violently when heated, and addition of concentrated sulfuric acid can result in flaming decompositions. There are many commercial diperoxyketals. and they are usually diluted willt solvents lor improved safety. 

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