On the Calcium Phosphate Banding in Silicic Acid Gel

Abstract

Abstract (1) The formation of rhythmic precipitate of calcium phosphate in a silicic acid gel was described. (2) The formation of this rhythmic precipitate was strongly affected by the hydrogen ion concentration of the gel. (3) The effects of the concentrations of inner and outer electrolytes, and gel on this rhythmic precipitate, were studied. (4) When the concentration of the inner electrolyte (CaCl2), was sufficiently great, no diffusion of the outer electrolyte into the gel took place but reversely calcium salt diffuse into the outer electrolyte solution and dendrities were formed in the outer solution. (5) The effect of the existence of a third substance in the gel and in the diffusing electrolyte, were also investigated. The existence of it in a diffusing electrolyte had almost no influence but the existence in a gel had some effects, especially in the case where bromide and iodide of potassium were used as the third substance.