base extraction

소개글

Organic chemistry lab report - base extraction

목차

Methods and Background
Experimental Procedures
Data Acquisition/Presentation
I. Relevant Equations
II. Summary of the solid masses that were obtained
Conclusion

본문내용

Physical State: white crystal Physical State: white crystal
In this experiment, we separated a binary mixture of acetanilide and benzoic acid by liquid-liquid extraction and recrystallized the extracts. We then purified each isolated solid by recrystillizing it from boiling water. We measured the melting points and compared to reported values. Finally, we calculated the % yield obtained for each solid based on the mass of starting mixture.
Liquid-liquid extraction is used widely to isolate and purify molecules from most chemical reaction. During this process, a solute is distributed between two immiscible liquids, extracting phase and original phase, when it comes to contact with them. How effective the extracting acid or base is depends on the Keq of the reaction. For an effective extracting acid or base the Keq must be greater than 1. In this case, most of the solute will be in the extracting



Conclusion
Recrystallization is used to purify solid or liquids. It occurs in two processes: extraction and filtration. During extraction, solutes are transferred from one solvent into another. The two solvents used in this lab were NaOH and CH2Cl2. Since dichloromethane is nonpolar only organic molecules like acetanilide will adhere to it. However, benzoic acid will adhere to the polar NaOH since like soluets dissolves in like solvents. These two solvents separate the solution into two distinct layers: organic layer and the aqueous layer. During extraction choosing the right solvents can make the process go faster. The best solvents are when the they are immiscible with the original solution, they do not react and form an equilibrium with the solutes in the mixture, they must remove the preferred component from the solution, and they must be easily separated from the solutes. After extraction comes filtration. This is when

참고 자료

Gilbert, J.C., Experimental Organic Chemistry, Saunders Publishing, New York, 2006, 4th Ed, pp. 75-81; 149-163; 93-100