Experiment 2: Recrystallization relies on differing solubilities of organic solids in a solvent. When a saturated solution of dissolved mixed organic solids is cooled, compounds that are least soluble will crystallize first. These purified crystals can be separated from remaining dissolved compounds by filtration. 1. What is the difference between precipitation and crystallization? Precipitation occurs when an insoluble compound is added to a solution resulting in a quick solidification of the salt in solution. This quick molecular construction can allow impurities to form in the newly formed solids. Crystallization is the process of slowly removing a given compound by cooling or displacing the solvent, and then allowing the molecules to gently reconfigure and recrystallize. Crystallization techniques also minimize impurities in the newly formed solid by keeping all impurities dissolved in the solvent. 2. Describe two negative consequences that could result from using vacuum
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This note was uploaded on 05/20/2011 for the course CHEM 262 taught by Professor Forbes during the Spring '08 term at UNC.