Acid-base chemistry aqueous solutions

Any acid that undergoes quantitative reaction with water to produce hydronium ions and the appropriate anion is called a strong acid. Table gives the structures and formulas of six common strong acids, all of which are supplied commercially as concentrated aqueous solutions. These solutions are corrosive and normally are diluted for routine use in acid-base chemistry. At the concentrations normally used in the laboratory, a solution of any strong acid in water contains H3 O and anions that result from the loss of a proton. Example shows a molecular view of the proton transfer reaction of a strong acid. 

The quantitative aspects of acid-base chemistry obey the principles Introduced earlier in this chapter. The common acid-base reactions that are important in general chemistry take place in aqueous solution, so acid-base stoichiometry uses molarities and volumes extensively. Example Illustrates the essential features of aqueous acid-base stoichiometry. 

Potassium hydrogen phthalate has many uses in analytical chemistry. It is a primary standard for standardization of bases in aqueous solutions. Its equivalent weight is 204.2. It also is a primary standard for acids in anhydrous acetic acid. Other applications are as a buffer in pH determinations and as a reference standard for chemical oxygen demand (COD). The theoretical COD of a Img/L potassium hydrogen phthalate is 1.176mg O2. 

Edward Koubek, "Acid-Base Chemistry of the Aluminum Ion in Aqueous Solution," J. Chem. Educ., Vol. 75,1998,60. 

Thomas JK (1967) Pulse radiolysis of aqueous solutions of methyl iodide and methyl bromide. The reactions of iodine atoms and methyl radicals in water. J Phys Chem 71 1919-1925 Tsang W, Hampson RF (1986) Chemical kinetic data base for combustion chemistry, part I. Methane and related compounds. J Phys Chem Ref Data 15 1086-1279 UlanskiP, von Sonntag C (1999) The OFI-radical-induced chain reactions of methanol with hydrogen peroxide and with peroxodisulfate. J Chem Soc Perkin Trans 2 165-168 Ulanski P, Bothe E, Hildenbrand K, von Sonntag C, Rosiak JM (1997) The influence of repulsive electrostatic forces on the lifetimes of polyfacrylic acid) radicals in aqueous solution. Nukleonika 42 425-436... 

Another approach for the preparation of dendrimer-noble metal nanoparticles in toluene is a process driven by acid-base chemistry and ion pairing [35]. At first, palladium nanoparticles are prepared by reducing aqueous K2PdCl4 with sodium borohydride in the presence of G4 dendrimer where the pH of dendrimer solution is adjusted to about 2. The low pH protonates the exterior amines to a greater extent than the less basic interior tertiary amines. Accordingly, Pd2+ binds preferentially to the interior tertiary amines and upon reduction palladium particles form within the dendrimer interior. After the complete reduction, the pH of solutions is adjusted back to about 8.5. Then, these nanocomposites can be quantitatively transported from the aqueous phase into toluene containing 10-20% of dodecanoic acid. The transition is visualized by the color change brown aqueous solution of dendrimer-palladium nanoparticles becomes clear after addition of the acid, while the toluene layer turns brown. 

The first person to recognize the essential nature of acids and bases was Svante Arrhenius. Based on his experiments with electrolytes, Arrhenius postulated that acids produce hydrogen ions in aqueous solution, and bases produce hydroxide ions. At the time of its discovery the Arrhenius concept of acids and bases was a major step forward in quantifying acid—base chemistry, but this concept is limited because it applies only to aqueous solutions and allows for only one kind of base—the hydroxide ion. A more general definition of acids and bases was suggested independently by the Danish chemist Johannes N. Bronsted (1879-1947) and the English chemist Thomas M. Lowry (1874-1936) in 1923. In terms of the Bronsted—Lowry definition, an acid is a proton (H+) donor, and a base is a proton acceptor. For example, when gaseous HCl dissolves in water, each HCl molecule donates a proton to a water molecule, and so HCl qualifies as a Bronsted-Lowry acid. The molecule that accepts the proton—water in this case—is a Bronsted-Lowry base. 

Much important chemistry, including most of the chemistry of the natural world, occurs in aqueous solution. We have already introduced one very significant class of aqueous equilibria, acid-base reactions. In this chapter we consider more applications of acid-base chemistry and introduce two additional types of aqueous equilibria, those involving the solubility of salts and the formation of complex ions. 

Mukhopadhyay B. and Walther J. V. (2001) Acid-base chemistry of albite surfaces in aqueous solutions at standard temperature and pressure. Chem. Geol. 174, 415-443. 

Acid-base chemistry was first satisfactorily explained in molecular terms after Ostwald and Arrhenius established the existence of ions in aqueous solution in 1880-1890 (after much controversy and professional difficulties, Arrhenius received the 1903 Nobel Prize in Chemistry for this theory). As defined at that time, Arrhenius adds form... 

AQUEOUS SOLUTIONS AND ACID-BASE CHEMISTRY Solution... 

AQUEOUS solutions AND ACID-BASE CHEMISTRY Sohtion... 

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