Recrystellization

The document provides information about recrystallization, including definitions, types of impurities, and the recrystallization process. It describes recrystallization as a method to purify organic compounds that are solids at room temperature by removing impurities. The key steps involve choosing a solvent based on solubility tests, dissolving the compound in hot solvent, slowly cooling the solution to form crystals of the pure compound, filtering and drying the crystals. Common solvents used in recrystallization are water, ethanol, methanol, hexanes and toluene. Care must be taken to use minimum amounts of hot and cold solvent to avoid losing product. The document also gives procedures for purifying phthalic acid and an unknown