Sulfuric acid thermodynamic properties

Physical Properties. Sulfuryl chloride [7791-25-5] SO2CI2, is a colorless to light yellow Hquid with a pungent odor. Physical and thermodynamic properties are Hsted ia Table 7. Sulfuryl chloride dissolves sulfur dioxide, bromine, iodine, and ferric chloride. Various quaternary alkyl ammonium salts dissolve ia sulfuryl chloride to produce highly conductive solutions. Sulfuryl chloride is miscible with acetic acid and ether but not with hexane (193,194). 

Values taken from S. Glasstone. Thermodynamics for Chemists. D. Van Nostrand Company Inc., Toronto, p. 443 (1947). The values tabulated in this reference were taken from D. N. Craig and G. W. Vinal, J. Res. Natl. Bur. Stand.. Thermodynamic Properties of Sulfuric Acid Solutions and Their Relation to the Electromotive Force and Heat of Reaction of the Lead Storage Battery", 24, 475-490 (1940). More recent values at the higher molality can be found in W. F. Giauque. E. W. Hornung. J. E. Kunzler and T. R. Rubin, The Thermodynamic Properties of Aqueous Sulfuric Acid Solutions and Hydrates from 15 to 300° K", J. Am. Chem. Soc.. 82, 62-70 (1960). 

It is convenient to use phase diagrams [46] to represent the thermodynamic properties that determine the stability and equilibrium composition of water-containing aerosols. The properties of interest are the temperature, the vapour pressure and composition of the various components in the condensed phases. This is particularly important with respect to the composition and stability of the various hydrates formed at low temperature in the nitric acid-water [47] and sulfuric acid-water binary systems [48], and the ternary systems HjSO/HNOj/HjO and HjSO/HCl/HjO [49],... 

Clegg SL, Brimblecombe P (1995) Application of a multicomponent thermodynamic model to activities and thermal properties of 0 40 mol kg 1 aqueous sulfuric acid from < 200 to 328K. J Chem Eng Data 40 43-64 Clegg SL, Rard JA, Pitzer KS (1994) Thermodynamic properties of 0-6 mol kg-1 aqueous sulfuric acid from 273.15 to 328.15K. Chem Soc Faraday Trans 90 1875-1894... 

A ubiquitous characteristic of vanadium chemistry is the fact that vanadium and many of its complexes readily enter into redox reactions. Adjustment of pH, concentration, and even temperature have often been employed in order to extend or maintain system integrity of a specific oxidation state. On the other hand, deliberate attempts to use redox properties, particularly in catalytic reactions, have been highly successful. Vanadium redox has also been successfully utilized in development of a redox battery. This battery employs the V(V)/V(IV) and V(III)AT(II) redox couples in 2.5 M sulfuric acid as the positive and negative half-cell electrolytes, respectively. Scheme 12.2 gives a representation of the battery. The vanadium components in both redox cells are prepared from vanadium pentoxide. There are two charge-discharge reactions occurring in the vanadium redox cells, as indicated in Equation 12.1 and Equation 12.2. The thermodynamics of the redox reactions involved have been extensively studied [8],... 

The data in Figures 33 and 34 show typical thermodynamic properties (normal Marcus region) for the electron transfer reaction. In these examples, the rate of the process increases as the driving force of the reation (—AGet) increases. The properties observed in Figures 33 and 34 also predict the type of radical formed after electron transfer. From studies of sulfur-containing amino acids and sulfur-containing carboxylic acids [170-175] it is known that decarboxylation occurs only if the carbox-... 

Numerous industrial applications of applied thermodynamics have been reported in the literature for engineering analysis of wide varieties of chemical systems and processes. For example, Chen and Mathias reported examples of physical property modeling for the high-density polyethylene process and for sulfuric acid plants. Here, we present two recent examples that are illustrative of numerous applications of applied thermodynamics models in the industry for various process and product development studies. 

Figure 12.18 Eh-pH diagram for aqueous species in the system S-02-H20 at 25°C neglecting sulfate, bisulfate, and elemental sulfur showing significant stability fields for sulfite and bisulfite, thiosulfate and its conjugate acid, and tetrathionate. Reprinted from Geochim. et Cosmochim. Acta, 56, M. A. Williamson and J. D. Rimstidt, Correlation between structure and thermodynamic properties of aqueous sulfur species, 3867-80, 1992, with permission from Elsevier Science Ltd., The Boulevard, Langford Lane, Kidlington 0X5 1GB, U.K.

Lustrous white, hard, ferromagnetic metal face-centered Cubic crystals, mp 1555". bp (calc) 2837" (3110 K) D. R. Stull. G. C. Sinke, Thermodynamic Properties of the Elements, Advances in Chemistry Series 18 (A.C.S.. Washington, 1956). d 8-90. Heat capacity (25 ) 6.23 cal/g -atom/°C. Mohs hardness 3-8. Latent heat of fusion 73 cal/g. Electrical resistivity (20 ) 6.844 uohms-cm. E taq) Ni/Ni2 0.250 V. Stable in air at ordinary temp burns in oxygen, forming NiO not affected by water decomposes steam at a red heat. Slowly attacked by dil hydrochloric or sulfuric acid readily attacked by nitric acid. Not attacked by fused alkali hydroxides. 

Phosphoric and sulfuric acid derivatives possess crucial properties that allow them to uniquely fill their many roles in biochemistry. Phosphoric acid may be esterified to form a monoester, diester, or triester (Figure 1). Sulfuric acid may be esterified at one or two positions, to form a monoester or a diester. Sulfate diesters are highly reactive, and have not been found in nature nor do phosphate triesters occur naturally. The hydrolysis of both phosphate and sulfate esters are thermodynamically favorable, but nucleophiles are repelled by the negative charge of the ionized forms. The resulting kinetic stability of phosphate monoesters and diesters, and of sulfate monoesters, is a major factor in their suitability for biological roles. For example, the half-life for hydrolysis of alkyl phosphate dianions by water is approximately 1.1 X 10 years k=2 x 10 s ) at 25°C. Such species... 

The calculation of the enthalpies of formation of organic sulfur compounds from the experimental results for their energies of combustion, requires an accurate knowledge of the enthalpy of formation of aqueous sulfuric acid. Enthalpies of formation of [H2SO4 n H2O] where n = 1 to 00 are available from the NBS Tables of Chemical Thermodynamic Properties [41]. The value usually taken for n in combustion calorimetry is n = 115 being Af//°([H2S04 115 H2OKI)) = -(887.811 0.042) kJmor. ... 

H2. Gardner, W.L. R.E. Mitchell, J.W. Cobble, "The thermodynamic properties of high-temperature aqueous solutions. X. The electrode potentials of sulfate ion electrodes from 0-100°. Activity coefficients and the entropy of aqueous sulfuric acid", J. Phys. Chem., v73, 6, pp2021-2024 (1969)... 

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