Anion characteristics

Hence, acids can be defined as substances producing cations characteristic of the solvent (solvo-cations, for example NH4, NO ), and bases as substances producing anions characteristic of the solvent (solvo-anions, for example OH , NH, NO3). This concept has been applied to solvents such as liquid sulphur dioxide, liquid hydrogen chloride and pure sulphuric acid. 

According to the Arrhenius theory of acids and bases, the acidic species in water is the solvated proton (which we write as H30+). This shows that the acidic species is the cation characteristic of the solvent. In water, the basic species is the anion characteristic of the solvent, OH-. By extending the Arrhenius definitions of acid and base to liquid ammonia, it becomes apparent from Eq. (10.3) that the acidic species is NH4+ and the basic species is Nl I,. It is apparent that any substance that leads to an increase in the concentration of NH4+ is an acid in liquid ammonia. A substance that leads to an increase in concentration of NH2- is a base in liquid ammonia. For other solvents, autoionization (if it occurs) leads to different ions, but in each case presumed ionization leads to a cation and an anion. Generalization of the nature of the acidic and basic species leads to the idea that in a solvent, the cation characteristic of the solvent is the acidic species and the anion characteristic of the solvent is the basic species. This is known as the solvent concept. Neutralization can be considered as the reaction of the cation and anion from the solvent. For example, the cation and anion react to produce unionized solvent ... 

The amphoteric behavior of Zn2+ and Al3+ in some nonaqueous solvents has already been described. This behavior can also be demonstrated in liquid S02. For example, the aluminum compound containing the anion characteristic of the solvent forms a precipitate, which is then soluble in either the acid or base in liquid S02. This can be shown as... 

Large cations give a favorable match of cation and anion characteristics, so in accord with the hard-soft interaction principle, the salts that have been isolated contain ions such as R4P+. Because of having an unshared pair of electrons, the SnX3" complexes can function as Lewis bases. 

Homoleptic platinum carbonyl anions, characteristics, 8, 410 Homoleptic tantalum complexes, preparation and characteristics, 5, 108... 

The charge-separation dynamics as deduced from the decays of the Fc radical cation and the C o radical anion characteristics as a function of donor-acceptor distance (Fig. 9.65) yielded a linear relationship. From the slope [1 was determined... 

Just as the cation produced by dissociation of water (H30+) is the acidic species in aqueous solutions, the NH4+ ion is the acidic species in liquid ammonia. Similarly, the amide ion, NH2, is the base in liquid ammonia just as OH- is the basic species in water. Generalization to other nonaqueous solvents leads to the solvent concept of acid-base behavior. It can be stated simply as follows A substance that increases the concentration of the cation characteristic of the solvent is an acid, and a substance that increases the concentration of the anion characteristic of the solvent is a base. Consequently, NH4C1 is an acid in liquid ammonia, and NaNH2 is a base in that solvent. Neutralization becomes the reaction of the cation and anion characteristic of the particular solvent to produce unionized solvent. For example, in liquid ammonia the following is a neutralization ... 

Arrhenius and Bronsted-Lowry acid-base neutralization reactions all have one thing in common. They involve the reaction of an acid with a base to form a salt that contains the cation characteristic of the base and the anion characteristic of the acid. Water is also usually formed. This is indicated in the formula unit equation. The general form of the net ionic equation, however, is different for different acid-base reactions. The net ionic equations depend on the solubility and extent of ionization or dissociation of each reactant and product. 

In a self-ionizing solvent, an acid is a substance that produces the cation characteristic of the solvent, and a base is a substance that produces the anion characteristic of the solvent. 

It should be noted that although the relative solubility in water can determine to a remarkable extent the mobility and bioactivity of the various substances, comparisons should be restricted to chemical substances with similar properties. Take, for example, paraquat, which can yield even a 70% solution, whereas the concentration of 2,4-D cannot exceed 650 ppm. The mobility of these two substances in the soil cannot, however, be estimated correctly from these data since paraquat is also present in its cationic form in water and it is strongly adsorbed by the soil, whereas 2,4-D exhibits anionic characteristics and it is only slightly adsorbed. In contrast to this, it is possible to compare the adsorption of chemically similar substances, such as phenurone and diurone. Those are both derivatives of phenylurea. Phenurone solubility in water is as large as 2900 ppm and it is much more mobile in water than diurone, which has a solubility of only 42 ppm. 

Solubility measurements on the platinum complex show that the difference in rra 5 -[PtCl2(PEt3)2] solvation on transfer is very small and certainly could not account for a change in rate of more than one power of ten. This conclusion is supported by the work of Drago, Mode and Kay. ° Belluco, Palazzi and Parker conclude that the platinum transition state, unlike the carbon transition state, is destabilised substantially in dimethylsulphoxide because the transition states are loose and the chloride ion retains much of its free anion characteristic, which allows it to contribute substantial interaction with the hydroxylic solvent despite its incorporation into a coordination position on the platinum. This is equivalent to saying that the negative charge on the transition... 

Sulfate sol- fat [F, fr. L sulfur] (1790) n. SO4. (1) A salt or ester of sulfuric acid. (2) A bivalent group or anion characteristic of sulfuric acid and the sulfates. 

Cady and Elsey gave the so-called solvent-system definitions, which depend on the mode of self-ionization of the particular solvent. Each solvent is considered as a parent of acids and bases. A solvo-acid is defined as a solute which increases the concentration of cations characteristic of the pure solvent and a solvo-base as a solute which increases that of the anions characteristic of the pure solvent ... 

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