Recrystallization Lab Report
Raquel Johnson
October 19, 2014
Solids: Recrystallization and Melting Points
Organic Chemistry 2423
Lab Report: Recrystallization
Abstract: The purpose of this lab was to purify an unknown compound by recrystallization. Taking an unknown compound and identifying it by purifying it from its impurities through the use of hot gravity filtration. Then to determine the unknown you were to take the melting point. An unknown compound was recrystallized from hot water to produce 0.99 grams (67% recovery). The pure unknown compound had a melting point of 127.0-128.9°C. The mixed melting point of the unknown with the benzoic acid was 107.9-109.1°C and with the 2-ethoxybenzamide was 127.5-128.4°C so the compound must be 2-ethoxybenzamide.
Introduction: This experiment was conducted in order to explore the methods of recrystallization and in order to determine the melting points of various solids. Recrystallization is to purify a solid by allowing it to recrystallize out the solution. The impurities stay in solution while the desired solid precipitates out. You have to dissolve a solute in a hot solvent and, then recrystallize the solute out of the cooled solvent. The formation of concentrated, pure crystals is possible in this recrystallization process if the appropriate cooling rate is applied to the solute and solvent mixture. Consequently, a purified, solid compound would be produced. Recrystallization involves dissolution of a solid in a solvent at elevated temperatures and the reformation of the crystals as the solution cools, allowing for impurities to remain in the solution. Once a solid has been recrystallized, it is important to determine the purity of the recrystallized solid.
Experimental Procedure:
Cautious:
- Vapors generated in this experiment are nasty. Carry out this experiment in the hood. Use caution when working with hot plates and hot solutions: it is easy to burn oneself when pouring boiling water or if one's solution bumps.
Procedure:
Part A:
October 19, 2014
Solids: Recrystallization and Melting Points
Organic Chemistry 2423
Lab Report: Recrystallization
Abstract: The purpose of this lab was to purify an unknown compound by recrystallization. Taking an unknown compound and identifying it by purifying it from its impurities through the use of hot gravity filtration. Then to determine the unknown you were to take the melting point. An unknown compound was recrystallized from hot water to produce 0.99 grams (67% recovery). The pure unknown compound had a melting point of 127.0-128.9°C. The mixed melting point of the unknown with the benzoic acid was 107.9-109.1°C and with the 2-ethoxybenzamide was 127.5-128.4°C so the compound must be 2-ethoxybenzamide.
Introduction: This experiment was conducted in order to explore the methods of recrystallization and in order to determine the melting points of various solids. Recrystallization is to purify a solid by allowing it to recrystallize out the solution. The impurities stay in solution while the desired solid precipitates out. You have to dissolve a solute in a hot solvent and, then recrystallize the solute out of the cooled solvent. The formation of concentrated, pure crystals is possible in this recrystallization process if the appropriate cooling rate is applied to the solute and solvent mixture. Consequently, a purified, solid compound would be produced. Recrystallization involves dissolution of a solid in a solvent at elevated temperatures and the reformation of the crystals as the solution cools, allowing for impurities to remain in the solution. Once a solid has been recrystallized, it is important to determine the purity of the recrystallized solid.
Experimental Procedure:
Cautious:
- Vapors generated in this experiment are nasty. Carry out this experiment in the hood. Use caution when working with hot plates and hot solutions: it is easy to burn oneself when pouring boiling water or if one's solution bumps.
Procedure:
Part A: