It is a well known fact that there are two distinct behaviours of dimorphism in which transitions are of reversible and irreversible natures. O. Lehmann was the first in classifying it by the two categories, enantiotropy and monotropy. Later it was interpreted by Ostwald and others on the basis of the phase theory. However, clear definitions have not been made so far, which are consistent with all the experimental cases in the wide range of pT-diagram. To make it more complete and concrete, some definitions are given for the terms enantiotropy and monotropy. These terms not only serve to express the absolute stability but also to express the mutual stability of the two modifications in one component. The thermodynamic relations connected to them are also described. The cases of pseudequilibrium are also spoken of. As the result of these considerations, various theories on enantiotropy and monotropy are brought into one conformity.
1. The oxidation of the mixture of sodium sulphite and stannous hydroxide in sodium carbonate solution was studied. 2. It was observed that the reaction is an example of negative induced reaction; the oxidation of stannous hydroxide has an inhibiting action on the oxidation of sodium sulphite. 3. The mechanism of the reaction was discussed.
1. The dissolution velocity of oxygen when air was passed into sodium hydroxide, sodium carbonate and hydrochloric acid solution under some conditions was calculated from the oxidation velocities of sodium sulphite, stannous hydroxide and stannous chloride. 2. The mechanism of some negative induced reactions was discussed.
1. The c-hydroxyl-group in hydroxyazo-compounds gives rise to two bands in their absorption carves. 2. The methyl-group shows perhaps no influence upon the shape of the absorption curves of hydroxyazo compounds.