Chemical Properties of Sulfuric Acid

The dominant chemical property of H2S04 is its strong acidity. Dissociation in the first step, 

When bisulfates are dissolved in water, the solutions are somewhat acidic because of the dissociation of the HS04 ion as shown in Eq. (15.125). 

Normal sulfates result from several processes including the following types of reactions  

Although the reaction of a sulfide is shown, sulfites and other sulfur-containing compounds can be oxidized to sulfates by using the proper oxidizing agents under the appropriate conditions. 

Most sulfates except those of Ca2+, Ba2+, Pb2+, Sr2+, and Eu2+ are soluble in water. Although H2SO4 does not normally react as an oxidizing agent, the hot, concentrated acid does behave in that way  

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This is a chemical reaction. The fact that iron reacts when it comes into contact with sulfuric acid is a chemical property of iron. Conversely, the ability of sulfuric acid to affect iron is a chemical property of sulfuric acid. The sulfuric acid and iron are called reactants in the above equation, and the iron sulfate and hydrogen are the products of the reaction. 

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. 

Obtaining data on the chemical and toxicological properties of sulfuric acid... 

The chemical properties of sulfur and its compounds are being widely utilized by the chemical industry. Sulfuric acid, in particular, has been regarded as the workhorse of the industry. By contrast, the mechanical properties of sulfur are largely unexploited, although it has been known for many years that sulfur does possess a number of interesting and potentially useful mechanical characteristics. 

Sulfur has been known since prehistoric times. Because it is flammable, alchemists regarded sulfur as essential to combustion. The chemical properties of sulfur and its compounds, including the reaction of sulfur with mercury (Hg) to form a red solid, mercuric sulfide (HgS), and the use of sulfuric acid (H2SO4) as a solvent of metals, were discovered at about C.E. 250-300. Gunpowder, a mixture of sulfur, charcoal, and potassium nitrate (KNO3), was first used for military purposes in China in C.E. 904. 

Chemical Properties. Although the chemical properties of the trivalent lanthanides are quite similar, some differences occur as a consequence of the lanthanide contraction (see Table 3). The chemical properties of yttrium are very similar too, on account of its external electronic stmcture and ionic radius. Yttrium and the lanthanides are typical hard acids, and bind preferably with hard bases such as oxygen-based ligands. Nevertheless they also bind with soft bases, typicaUy sulfur and nitrogen-based ligands in the absence of hard base ligands. 

Chemical Properties. MSA combines high acid strength with low molecular weight. Its pK (laser Raman spectroscopy) is —1.9, about twice the acid strength of HCl and half the strength of sulfuric acid. MSA finds use as catalyst for esterification, alkylation, and in the polymerisation and curing of coatings (402,404,405). The anhydrous acid is also usefijl as a solvent. 

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). 

The corrosion behavior of tantalum is weU-documented (46). Technically, the excellent corrosion resistance of the metal reflects the chemical properties of the thermal oxide always present on the surface of the metal. This very adherent oxide layer makes tantalum one of the most corrosion-resistant metals to many chemicals at temperatures below 150°C. Tantalum is not attacked by most mineral acids, including aqua regia, perchloric acid, nitric acid, and concentrated sulfuric acid below 175°C. Tantalum is inert to most organic compounds organic acids, alcohols, ketones, esters, and phenols do not attack tantalum. 

Snatzke has found that a solution prepared from chromium trioxide and dimethylformamide with a small amount of sulfuric acid has similar chemical properties as the Sarett reagent. It is useful with acid sensitive compounds and oxidation occurs at such a moderate rate that selective oxidations are often possible. Although the position allylic to a A -double bond is not attacked, the 3-hydroxy-A -system cannot be oxidized satisfactorily to the cor-... 

As has been suggested in the previous section, explanations of solvent effects on the basis of the macroscopic physical properties of the solvent are not very successful. The alternative approach is to make use of the microscopic or chemical properties of the solvent and to consider the detailed interaction of solvent molecules with their own kind and with solute molecules. If a configuration in which one or more solvent molecules interacts with a solute molecule has a particularly low free energy, it is feasible to describe at least that part of the solute-solvent interaction as the formation of a molecular complex and to speak of an equilibrium between solvated and non-solvated molecules. Such a stabilization of a particular solute by solvation will shift any equilibrium involving that solute. For example, in the case of formation of carbonium ions from triphenylcarbinol, the equilibrium is shifted in favor of the carbonium ion by an acidic solvent that reacts with hydroxide ion and with water. The carbonium ion concentration in sulfuric acid is greater than it is in methanol-... 

Crookesite. In 1866 Baron Nils Adolf Erik Nordenskiold found among the collections at the Royal Museum in Sweden a rare mineral from Skrikerum, which C. G. Mosander had regarded as a copper selenide. When Baron Nordenskiold analyzed it, he found it to be a selenide of copper, silver, and thallium. Because it was the first mineral of which the recently discovered element thallium was shown to be an essential constituent, he named it crookesite in honor of Sir William Crookes, the discoverer of thallium (31). Although crookesite is very rare, selenium and thallium are often found associated in nature, and both of these elements, so different in chemical properties, were originally discovered in the same source, namely the slime in the lead chambers of sulfuric acid plants using seleniferous and thalliferous pyrite. 

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