Evaporation influences on the crystallization of an aqueous dihydrate cupric chloride solution with additives

The overall structure of the crystallization results of dihydrate cupric chloride with additives in a petri dish is affected by the duration between the beginning of the evaporation and the start of the crystallization. Experiments done with polyvinylpyrrolidone and freeze-dried carrot as additive are compared with those of the additive free case. The dependecy of dewetting on the dihydrate cupric chloride amount is discussed in terms of depletion of the solution and the surface tension properties of the system. The possible influence of the depletion is depending on the moment the crystallization starts. This is defined by the size of the evaporated area on the dish.