Holding power, explaining

One route into thinking about chemical bonding is in terms of the states of matter (the (submicroscopic) structures that different solid substances take) and the properties of different substances. As Chapter 2 points out, different substances undergo phase changes (solid to liquid liquid to gas) at very different temperatures. We also find that substances have different behaviours if we try to dissolve them in solvents, or pass electricity through them, for example. These differences in behaviour present the chemist with phenomena to be explained, and provide the chemistry teacher with one basis for exploring the nature of the holding power students learn about early in their secondary chemistry. 

It should also be acknowledged that in recent years computational quantum chemistry has achieved a number of predictions that have since been experimentelly confirmed (45-47). On the other hand, since numerous anomalies remain even within attempts to explain the properties of atoms in terms of quantum mechanics, the field of molecular quantum mechanics can hardly be regarded as resting on a firm foundation (48). Also, as many authors have pointed out, the vast majority of ab initio research judges its methods merely by comparison with experimental date and does not seek to establish internal criteria to predict error bounds theoretically (49-51). The message to chemical education must, therefore, be not to emphasize the power of quantum mechanics in chemistry and not to imply that it necessarily holds the final answers to difficult chemical questions (52). 

The different behaviour of various textile fibres in dyeing may be explained by an assumption of different solvent power thus, silk dyes more readily than other fibres because the fibroin has a greater solvent power. Keratine again, the principle of the wool fibre, possesses a greater solvent power than cellulose, which is only capable of attracting and holding in solution a few dyestuffs, such as the tetrazo-dyes of the benzidine series, and in certain cases in this class the solvent power of the water in the dye-bath has to be decreased by addition of salt. 

The catalytic effect of the nitric acid gas has been attributed to (a) increase in the concentration of active oxygen and (b) greater oxidizing power of nitrogen peroxide.27 The formation of phenol from benzene by electrochemical oxidation has been explained on the basis of atomic oxygen,18 a hypothesis that may hold in this case. A mechanism for the catalytic effect of nitrogen peroxide based on the conclusion that it is readily activated by the absorption of radiation over a relatively wide range of frequencies is as follows ... 

A most surprising behavior was found when the polarization current of a corroding specimen was observed as a function of flow rate. Fig.20 shows the results which were obtained. Anodic and cathodic polarization currents in milliamps at potentials of 50 millivolts from the corrosion potential are plotted against flow rate. In several runs reproducible behavior was observed. The cathodic current varies with flow rate to the th power, while the anodic current varies with flow rate to the th power. This relationship holds true over more than one decade of flow rates. It is very difficult to explain such results in terms of conventional mass transfer limitations. It is well known that the diffusion limited current varies approximately proportionally to the flow rate in the turbulent region and with the square root of flow rate in the laminar region. If on the other hand the polarization current was transport limited across the corrosion... 

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