As weak acid

Since the hydrogen-element bond energy decreases from sulphur to tellurium they are stronger acids than hydrogen sulphide in aqueous solution but are still classified as weak acids—similar change in acid strength is observed for Group Vll hydrides. 

Organohthium and organomagnesium compounds are stable species when prepared m suitable solvents such as diethyl ether They are strongly basic however and react instantly with proton donors even as weakly acidic as water and alcohols A proton is transferred from the hydroxyl group to the negatively polarized carbon of the organometallic compound to form a hydrocarbon... 

Aminophenols and their derivatives are of commercial importance, both in their own right and as intermediates in the photographic, pharmaceutical, and chemical dye industries. They are amphoteric and can behave either as weak acids or weak bases, but the basic character usually predominates. 3-Aminophenol (2) is fairly stable in air unlike 2-aminophenol (1) and 4-aminophenol (3) which easily undergo oxidation to colored products. The former are generally converted to their acid salts, whereas 4-amiaophenol is usually formulated with low concentrations of antioxidants which act as inhibitors against undesired oxidation. 

Alcohols can act either as weak acids or as weak bases, just as water can. Show the reaction of methanol, CH jOH, with a strong acid such as f-ICl and with a strong base such as Na -N112. 

As weak acids, they dissociate slightly in dilute aqueous solution by-donating a proton to water, generating H O+ and an alkoxide ion, RO-, or a phenoxide ion, ArO-. 

A wide variety of solutes behave as weak acids that is, they react reversibly with water to form H30+ ions. Using HB to represent a weak acid, its Bronsted-Lowry reaction with water is... 

You may be surprised to learn that many metal cations act as weak acids in water solution. A 0.10 M solution of A12(S04)3 has a pH close to 3 you can change the color of hydrangeas from red to blue by adding aluminum salts to soil At first glance it is not at all obvious how a cation such as Al3+ can make a water solution addic. However, the aluminum cation in water solution is really a hydrated species, A1(H20)63+, in which six water molecules are bonded to the central Al3+ ion. This spedes can transfer a proton to a solvent water molecule to form an H30+ ion ... 

As we pointed out in Section 13.4, certain cations act as weak acids in water solution because of reactions such as... 

Essentially all transition metal ions behave like Zn2+, forming a weakly acidic solution. Among the main-group cations, Al3+ and, to a lesser extent, Mg2+, act as weak acids. In contrast the cations in Group 1 show little or no tendency to react with water. 

Most of the nitrated product is in the form of an emulsion and consequently is much safer to handle. The toluene that enters stage 1 leaves stage 7 as crude TNT, while the strong acid that enters stage 7 comes out as weak acid in stage 1. Man-power requirements are kept to a minimum even for 10 million pounds/year production... 

N 24.12% brick red solid mp, decomps when heated over 300°. Insol in w and the usual organic solvents as well as weak acids and alkalies. Comm prepn (Ref 3) is from thiocyanic acid and/or thiocyanates either by anodic oxidation or by interaction with hydrogen peroxide or halogens. The yield is impure because it contains both H and O. The S content varies between 45 and 55%. Lab prepn of the pure polymer is by reacting the Na salt of 5-chlor-3-mercapto 1,2,4-thiodiazols with either acet, ethanol or w (Refs 1 2)... 

Salts dissolve in water with dissociation of the constituent ions, this concept having been proposed originally by S. Arrhenius in 1887. His first idea was that all salts, including those of what would now be regarded as weak acids or bases, are completely dissociated at extreme dilution (Hall, 1985). It was eventually realized that substances such as NaCl, KCl, etc, are effectively completely dissociated at all concentrations. 

Formazans behave as weak acids as well as weak bases. Salts of formazans have been isolated.26,334,335 The acid dissociation constants of some substituted formazans have been determined from their solution spectra.336... 

Ion chromatography has become available and is used for sugar analysis. In this system a high-performance anion exchange column is used at high pH. This separation works because neutral saccharides behave as weak acids. Table 1 shows some pKa values. 

Hydrated metal ions act as weak acids by donating a proton. For example, Fe becomes hydrated with six water molecules, [Fe(OH2)6l. Write an equation to illustrate how the hydrated iron(II) ion acts as an acid in aqueous solution. 

POMs are resistant to many solvents including aqueous salt and alkaline solution, as well as weak acids. 

Oxide surfaces are high-energy surfaces that interact with water molecules becoming covered by a carpet of OH groups. The latter, in contact with aqueous solutions, behave as weak acids or weak bases, giving rise to dissociation that is the main origin of surface charging ... 

Since proteins contain a lot of acidic and basic side chains acting as weak acids and bases, respectively, proteins are buffering substances, too. If you mix buffer solutions with protein solutions, pH may be altered because the concentration of protein s buffering residues may exceed the capacity of the (chemical) buffer. For instance, bovine serum albumin contains 59 basic (Lys) and 99 acidic (59 Asp plus 40 Glu) residues per mole a solution of 10 mg/ml (1%) BSA contains 9 mM basic and 14.5 mM acidic residues, and phosphate-buffered saline (PBS) contains only 10 mM phosphate. As a consequence of this example (a) the concentration of the chemical buffer should be high enough to act as a buffer, (b) choose a chemical buffer the pK of which is nearby the pH to be stabilized, and (c) adjust the pH after all components are mixed. 

Using bulk average composition to assess the chemistry of fogs and clouds can be misleading in other respects as well. For example, Pandis and Seinfeld (1991, 1992) show that the bulk mixture formed from drops with different pH values that are each in equilibrium with the gas phase does not itself conform to Henry s law, with the bulk mixture being supersaturated with respect to species such as weak acids and... 

Amines are the most important organic bases as well as weak acids. Thus, an amine can behave as an acid and donate a proton, or as a base and accept a proton. 

D. K. Hale D. Reichenberg Development of carboxylic addition polymers as weak acid cation exchangers. 1949-1956... 

Thus, in the acidic areas of the tract such as the stomach (pH 1-3), compounds that are lipid soluble in the nonionized form, such as weak acids, are absorbed, whereas in the more alkaline (pH 6) small intestine, weak bases are more likely to be absorbed. The fact that in practice weak acids are also absorbed in the small intestine despite being ionized (Fig. 3.15) is due to the following ... 

In addition, some acids which behave as weak acids in water (with pKa up to about 12) react completely with ammonia and hence are strong acids in this solvent ... 

Aqueous solutions of the +2 and +3 metal salts of strong acids are always slightly acid. This would probably seem reasonable to you if you reasoned from our general statement about the hydrolysis of salts on p 358, assuming that the metal ions come from weak bases (though they are actually insoluble ). A more satisfactory explanation is that hydrated aquo metal ions can act as weak acids. For example, hexaaquo iron(III) could dissociate to give... 

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