The Theory and Application of Colloidal Behavior: Contributed by the Foremost Authorities in Each Division of the Subject, Volume 1

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Robert Herman Bogue
McGraw-Hill Book Company, 1924
 

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Page 150 - If the stray field of a molecule, that is of a complex of these atomic systems, be unsymmetrical, the surface layer of fluids and solids, which are close-packed states of matter, must differ from the interior mass in the orientation of the axes of the fields with respect to the normal to the surface, and so form a skin on the surface of a pure substance having all the molecules oriented in the same way instead of purely in random ways.
Page 155 - ... we suppose the structure of the surface of a liquid to be at first the same as that of the interior of the liquid, then the actual surface is always formed by the orientation of the least active portion of the molecule toward the vapor phase, AND AT ANY SURFACE OR INTERFACE THE CHANGE WHICH OCCURS IS SUCH AS TO MAKE THE TRANSITION TO THE ADJACENT PHASE LESS ABRUPT.
Page 151 - The surface energy of a liquid is thus not a property of the group molecules, but depends only on the least active portions of the molecules and on the manner in which these are able to arrange themselves in the surface layer. "In liquid hydrocarbons of the paraffin series the molecules arrange themselves so that the methyl groups (CH3) at the ends of the hydrocarbon chains form the surface layer.
Page 150 - ... matter, must differ from the interior mass in the orientation of the axes of the fields with respect to the normal to the surface, and so form a skin on the surface of a pure substance having all the molecules oriented in the same way instead of purely in random ways. The result would be the polarisation of the surface, and the surface of two different fluids would attract or repel one another according to the sign of their surfaces.
Page 296 - It is evident that, in this experiment, the hydrogenation was, practically exclusively, hydrogenation of linolic acid glycerides and negligible hydrogenation of oleic acid compounds. This would indicate almost exclusive adsorption of the more highly unsaturated glycerides at the nickel surface. The authors found that the selectivity of the hydrogenation appears to be more marked with increasing amounts of catalyst and with increasing temperature up to an optimum in the neighborhood of 200°C.
Page 24 - As gelatin appears to be its type, it is proposed to designate substances of the class as colloids, and to speak of their peculiar form of aggregation as the colloidal condition of matter.
Page 2 - When equilibrium is established, if a small virtual change is made reversibly at constant temperature and volume, the free energy will remain unchanged; that is, no work will be done. The change here considered is the transfer of dn mols of Na+ and Cl
Page 197 - OH, while the interior consists of the long hydrocarbon chains. The size of the colloidal particles is determined by the difference in size between the two ends of the molecules just as the size of an arch is dependent upon the relative sizes of the two ends of the stones of which the arch is constructed.
Page 24 - Although often largely soluble in water, they are held in solution by a most feeble force. They appear singularly inert in the capacity of acids and bases, and in all the ordinary chemical relations. But, on the other hand, their peculiar physical aggregation, with the chemical indifference referred to, appears to be required in substances that can intervene in the organic processes of life.
Page 24 - ... gelatine, vegetable and animal extractive matters. Low diffusibility is not the only property which the bodies last enumerated possess in common. They are distinguished by the gelatinous character of their hydrates. Although often largely soluble in water, they are held in solution by a most feeble force. They appear singularly inert in the capacity of the acids and bases, and in all the ordinary chemical relations.

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