University of South Florida CHM 2210L Simple and Fractional Distillation of a Binary Mixture Post-Lab Report 2024 Complete

Florida CHM 2210L Simple and Fractional Distillation of a Binary Mixture Post-Lab Report 2024 Complete What is distillation? separation of liquids based on boiling point differences Explain the procedure in simple/fractional distillation 1. Set-up the simple/fractional distillation apparatus - heat source (hot plate or bunsen burner + wire gauze), distilling flask, column, condenser, receiving flask 2. Place 20 mL n-hexane + 20 mL toluene in 100 mL round bottom flask 3. Start distillation What are the reagents used in simple/fractional distillation? n-hexane (C6H14), 20 mL toluene (C7H8), 20 mL Parts of a simple/fractional distillation setup heat source, distilling flask, air column, thermometer, holder, condenser, receiver When does boiling occur? When the vapor pressure of liquid is the same of atmospheric pressure When is simple distillation and fractional distillation used? Simple distillation: boiling point difference is > 25 deg C; bp < 150 Fractional distillation: boiling point difference is < 25 deg C both are used for separating miscible liquids Which is more efficient: longer or shorter fractionating column? Longer - better spread of temperature, higher purity Shorter - the longer the distill lasts in terms of life span - A longer column would give a purer distillate. The longer the vapors take to reach the top of the column, the higher the purity of the fraction, and the more efficient the column Why is better separation of two liquids achieved by slow rather than fast distillation? - Usually, faster distillation means higher temperature, which could cause the mixture not to separate as much due to it being more prone to evaporation. - if you distill too quickly, it is easy to overrun the first boiling point and get a lot of unwanted impurities - The longer the vapors take to reach the top of the column, the higher the purity. Repeated distillation (by the use of a column with greater SA) also increases purity. In a fractional distillation, is the composition of the vapor just above the surface of the liquid the same as the vapor near the thermometer bulb? Explain. No. The higher the vapor in the column, the purer it is. The vapor near the thermometer bulb is more pure than the vapor above the surface of the liquid. As vapors continue to rise through the column, the liquid that has condensed will revaporize. Each time this occurs the resulting vapors are more and more concentrated in the more volatile substances.