Estopace, Edgie1, Polintan, Clarisse K.
Professor Edgie Estopace, School of Chemical Engineering, Chemistry and Biotechnology, Mapua Institute of Technology; Clarisse Polintan, CHM145L/A21, School of Chemical Engineering, Chemistry and Biotechnology, Mapua Institute of Technology
ABSTRACT
This experiment is all about identifying the appropriate solvent for recrystallization and technique and to use the recrystallization technique in purifying a solid sample. Most organic substances are impure and require techniques in order to purify a sample. One of these techniques to make an impure sample pure is by recrystallization. This experiment includes the determination of a good solvent for recrystallization for compounds such as: acetanilide, acetamide, aspirin, benzoic acid, naphthalene, and sucrose, for solvents such as: water, ethanol, benzene, and ethyl acetate. Also pure acetanilide is achieved. here are five major steps in the recrystallization process: dissolving the solute in the solvent, performing a gravity filtration, if necessary, obtaining crystals of the solute, collecting the solute crystals by vacuum filtration, and, finally, drying the resulting crystals giving us the pure sample of the compound. The best solvent used for each of the compounds listed and the percentage recovery of the crude acetanilide. The physical properties of the compound were also determined.
INTRODUCTION
Differential solubility is defined as the differences in the amount of solid that can be dissolved in an appropriate solvent as affected by variations in temperature. Solubility is inversely proportional to its temperature, since most solids have solubilities that are lower in liquid solvents at low temperatures. Differences in solubilities are sometimes used in the process of obtaining pure compounds by dissolving the solid in hot solvent and allow the undissolved impurities to be filtered off. The filtrate would then be cooled down and
References: 1. Baluyut, J.Y.G., and De Castro, K. A., Organic Chemistry Laboratory Manual For Chemistry Students Part1. 2. Klein, D., (2011) Organic Chemistry, 1st Ed., Cold United States of America