Preparation of Chemical Substances for Analysis

Herout, V., and Protiva, M. Laboratoriumstechnik der organischen Chemie Akademie Verlag, Berlin, 1961. 

Cheronis, N. D. Micro and Semimicromethods. Vol. 6 Weissberger (Editor), Techniques of Organic Chemistry. Interscience, New York 1954. 

and Zacherl, M. K. (Editors) Handbuch der mikrochemischen Me-thoden. Springer, Vienna 1954. 

Crystallization is one of the most efficient purification operations for solid organic substances. The analyst uses it both for the purification of the sample before the analysis, and for the preparation of derivatives necessary for the final determination of basic constants. 

When looking for a suitable solvent one should proceed according to basic experience, according to which a definitely nonpolar substance (for example, a hydrocarbon) is best soluble in nonpolar solvents (for 

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