Influence of Supersaturation on the Kinetics of Crystallisation of ZnC204 . 2 H20
The kinetics of crystallisation of ZnC,04. 2 H,O was investigated at 25 "C and at different supersaturations. Zinc oxalate was prepared from pure zinc sulphate a.nd oxalic acid solutions. The specific surface energy at the crystal-solution interface was calculated from the induction period and the Volmer relationship, while the critical nuclei dimension was found by means of the Thomson-Gibbs equation. With the decrease in supersaturation the size of t,he nuclei does not increase to infinity, but changes by 1 -2 unit cells within a given supersaturation range.
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