Purifying Acetanilide by Recrystallization

Purifying Acetanilide by Recrystallization

Four test tubes of 13x100 were obtained and labeled "Acetone", "Water", "Ethanol", and "Petroleum Ether." Approximately 100 mg of Acetanilide and 2.0 ml of appropriate solvent were added in each test tube. The test tubes were stirred thoroughly. After stirring, it was observed that in which solvent acetanilide is insoluble at room temperature. The insoluble test tubes were heated to boiling using the sand bath and were cooled to room temperature. Later, it was observed in which solvent acetanilide was soluble. The resulting solvent was further used for the experiment.

After finding which solvent to use, .500 grams of acetanilide was weighed in to a 50 ml Erlenmeyer flask. Shortly after, the resulting solvent was added to make the solid swirable. The mixture was heated to boiling using the sand bath and when all the solid dissolved, the solution was set to cool a little. When the solution was cooled down, a small amount of charcoal was added and was heated to boiling. The resulting solution was then filtered by using the gravity filtration method. Then the filtered solution was cooled in an ice-water bath for a few minutes to maximize crystal formation. At last the vacuum filtration method was set up, with vacuum applied; the solution containing the suspended crystals was poured onto the filter paper so that uniform of thickness of crystal is collected on the filter paper. After the mother liquor was being pulled through the filter, the crystals were washed with small portions of cold solvent. At last crystals were dried in an open container for one week. After one week the mass was measured.