Of sulfuric acid solutions

Figures 5 and 6 present the electrical conductivity of sulfuric acid solutions (51,52). For sulfuric acid solutions in the 90—100% H2SO concentration range, the electrical conductivity measurements reported by Reference 52 are beheved to be the best values other conductivity data are also available...

The viscosity of sulfuric acid solutions is plotted in Figure 7 (55) other viscosity data may be found in References 54—60. Surface tension of sulfuric acid solutions is presented in Figure 8 (61). Surface tension of selected concentrations of sulfuric acid as a function of temperature up to the boiling point is given in Reference 62 other data are also available (58,59,63—65). 

The index of refraction of sulfuric acid solutions (62) and additional related data (66), along with solubiUty data for oxygen in sulfuric acid solutions (67), are available in the Hterature. The solubiUty of sulfur dioxide in concentrated sulfuric acid is shown in Figure 9 (68) additional data are also available (69). 

Data on chemical properties such as self-dissociation constants for sulfuric and dideuterosulfuric acid (60,65,70,71), as well as an excellent graphical representation of physical property data of 100% H2SO4 (72), are available in the Hterature. Critical temperatures of sulfuric acid solutions are presented in Figure 10 (73). 

Materials of Construction. Resistance of alloys to concentrated sulfuric acid corrosion iacreases with increasing chromium, molybdenum, copper, and siUcon content. The corrosiveness of sulfuric acid solutions is highly dependent on concentration, temperature, acid velocity, and acid impurities. An excellent summary is available (114). Good general discussions of materials of constmction used ia modem sulfuric acid plants may be found ia References 115 and 116. More detailed discussions are also available (117—121). For nickel-containing alloys Reference 122 is appropriate. An excellent compilation of the relatively scarce Hterature data on corrosion of alloys ia Hquid sulfur trioxide and oleum may be found ia Reference 122. 

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). 

The seepage and leaking of sulfuric acid solutions used in leaching can also produce liquid wastes however, this potential is offset by the copper producer s interest in collecting as much of the copper-bearing leachate as possible. Older operations generally do not have protective liners under the piles and experience some loss of leachate. New leaching operations use impermeable membranes to confine leach solutions and channel them to collection ponds. 

EXAMPLE 2.25. What mass in grams is present in 10.0mL of sulfuric acid solution, which has a mass of 1.86g for every 1.00 mL ... 

Figure 32. Variation of the lowering of the surface free energy of sulfuric acid solutions, with acid concentration, by the racemic ( ) and enantiomeric (A) -a-methyl-benzylstearamides. From Thompson (101).

Trifluoroacetic acid (CF3CO3H) sits between peroxyacetic acid and peroxydisulfuric acid in oxidizing potential. Anhydrous solutions of peroxytrifluoroacetic acid in methylene chloride can be prepared by the addition of 90 %+ hydrogen peroxide to a solution of trifluoroacetic anhydride in methylene chloride containing a trace of sulfuric acid. Solutions of peroxytrifluoroacetic acid prepared from less concentrated hydrogen peroxide solution or trifluoroacetic acid are less reactive to arylamines. 

A — cc of sodium hydroxide solution usod B = Normality of sodium hydroxide solution C = cc of sulfuric acid solution used D = Normality of sulfuric acid used E = Weight of sample used... 

Furthermore, given a solution of molar acid concentration, x, a generatrix function, MJ x) is defined (77JCS(P2)309) as a series expansion in x (the first analysis was that of sulfuric acid solutions). Equation (38) is satisfied to a good approximation and pKbh+ values are determined according to... 

At atmospheric pressure, sulfuric acid has a maximum boiling azeotrope at approximately 98.48% (78,79). At 25°C, the minimum vapor pressure occurs at 99.4% (78). Data and a discussion on the azeotropic composition of sulfuric acid as a function of pressure can also be found in these two references. The vapor pressure exerted by sulfuric acid solutions below the azeotrope is primarily from water vapor above the azeotropic concentration S03 is the primary component of the vapor phase. The vapor of sulfuric acid solutions between 85% H2S04 and 35% free S03 is a mixture of sulfuric acid, water, and sulfur trioxide vapors. At the boiling point, sulfuric acid solutions containing <85% H2S04 evaporate water exclusively those containing >35% free S03 (oleum) evaporate exclusively sulfur trioxide. 

The authors believe that the decreases in decay times are associated primarily with changes in quantum yield. This may be inferred from the fact that both the emission intensities and lifetimes are falling off at about the same rate with temperature. One thus concludes that the luminescence of sulfuric acid solutions of terbium sulfate is subjected to much greater temperature quenching than the luminescence in aqueous solution of the same salt. The increasing probability of radiationless transitions is undoubtedly connected in some manner with greater interaction of the radiating ion with the solvent molecules. 

Letw = mass (weight) of sulfuric acid solution. Also, notice that there are 58.0 grams of pure acid per 100 grams of solution (58.0% H2SO4 solution). 

Finally, we determine the amount of sulfuric acid solution containing 90.0% H2SO4 that contains 565 kg of pure H2SO4. We now know that 0.900 kg of pure H2SO4 makes 1 kg of 90.0% solution. Then... 

Lead Transfer 4.0 g of sample to an evaporating dish, add 4 mL of sulfuric acid solution (1 4), distributing it evenly throughout the sample, and evaporate most of the water on a steam bath. Char and dehydrate the sample by heating on a hot plate, while at the same time, heating with an infrared lamp from above, and then heat in a muffle furnace at 500° until the residue is free from carbon. Remove the dish from the furnace, cool, and cautiously wash down the inside of the dish with water. Add 1 mL of 1 A hydrochloric acid, evaporate to dryness on a steam bath, then add 2 mL of 1 A hydrochloric acid, and heat briefly, while stirring, on a steam bath. Quantitatively transfer the solution into a separator with the aid of small quantities of water, and neutralize with 1 A ammonium hydroxide. This Sample Solution meets the requirements of the Lead Limit Test, Appendix IIIB, using 4 pg of lead (Pb) ion in the control. 

How many grams of sulfuric acid solution (98%) must act on an excess of zinc to produce 12.0 m3/hr of hydrogen at standard conditions. Assume all the acid used completely reacts. 

Absorption Maxima of Sulfuric Acid Solutions of Halogenated... 

HCIO4. The radical character was demonstrated by ESR. Its UV and visible spectra in solutions are identical to those of sulfuric acid solutions of chlorpromazine, which ESR showed to contain radical species. 

The acidic properties of sulfuric acid solutions are discussed in Section 7.7. 

It will be observed that according to the suggested cell reaction, two molecules of sulfuric acid should be removed from the electrolyte and two molecules of water formed for the discharge of two faradays of electricity from the charged cell. This expectation has been confirmed experimentally. Further, it is possible to calculate the free energy of this change thermodynamically in terms of the aqueous vapor pressure of sulfuric acid solutions the values should be equal to — 2FEy where E is the E.M.F. of the cell and this has been found to be the case. 

The photochemical method of ozone production gives rather low energy yields in comparison to the two methods used industrially—viz., by silent electric discharge or by electrolysis of sulfuric acid solutions. 

To produce crude aluminum sulfate containing 1798 lb of pure aluminum sulfate, 1080 lb of bauxite ore and 2510 lb of sulfuric acid solution are used. 

Sulfuric acid can be found in many strengths and formulations. Toxicological and chemical properties of sulfuric acid solutions are dependent on the sulfuric acid content of the solution. For example, solutions containing less than 10% sulfuric acid are highly irritating, while solutions containing more than 10% sulfuric acid are corrosive. Sulfuric acid solutions used in industry can be up to 98% in concentration, while consumer products such as toilet bowl cleaners may contain up to 8% sulfuric acid. 

The relative apparent molar heat contents of sulfuric acid (solute) in mixtures with water (solvent), for various compositions at 25° C, are recorded in Table XXXVl. It may be noted that when L is positive, is negative, and the dilution process is accompanied by the evolution of heat. It is seert, therefore, from Table XXXVI that heat is evolved upon the infinite dilution of sulfuric acid solutions at all concentrations down to the lowest studied, viz., 0.00108 molal. 

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