Use a 5-mL round bottom flask, measure alcohol and carboxylic acid precisely that was calculated in the prelab. Add sulfuric acid (4 drops) with caution and mix them using a clean pipet and expelling them back into the flask. Mixing well is required so it will not result in the concentrated sulfuric acid reacting to form unwanted darkly colored by-products. Add a few boiling chips and go through distillation. Trapping the water is more effective if the side arm points slightly downward when the round block flask with distillation head attached is held in an upright position in a 45-degree angle. Sand bath is then used to boil. Vapors should condense about 1/3 way up the reflux condenser. Overheating can make product and reactants to escape into the atmosphere. Two phases of liquid will collect in the side arm, upper organic phase and lower water phase. Remove water, after the reaction has refluxed for 15 minutes, raise the apparatus from heat and tip it back so that most of the upper phase in the side arm drips. Lower the apparatus back and using sand bath, resume refluxing for 15 minutes, then again lift and tip it back. Reflux for the 3rd and last time to make it 45 minutes total. Then cool it completely for 15 minutes. Take cooled content and use a pipet into a centrifuge containing water (1 mL). Mix well, lower layer to the top, remove the aqueous layer and place it into a beaker. Add sodium bicarbonate (1 mL), mix well, and remove the aqueous layer once again. Add 5 spheres of anhydrous calcium chloride to the liquid and swirl. Using a pipet, take organic layer into a vial and all the spheres should not clump together. Add more spheres if they are clumping together. Using a pipet transfer the liquid to a dry tared capped vial. Smell ester and check the odors of different esters made by classmates. Determine % yield of product, determine and interpret the IR spectrum. For comparison, check the IR spectra of a carboxylic acid, an alcohol, and an ester.
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