Experiments of neutralization with aqua ammonia

The results shown in Fig. 15.4 are very interesting like the titration curve in the volumetric analysis, there is a mutation point on the pH curve of the reaction mixture versus the amount of aqua ammonia added. This is opposite to the property of a buffer solution. 

Although it is difficult to precisely explain the phenomena illustrated in Figs. 15.3 and 15.4 at present, the information contained in these figures is helpful for further analysis and investigation on the mechanism and regularities of the reaction-precipitation process, and for searching for a possible method for size-control of the product. 

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