A one to one mixture of alcohol and carboxylic acid will usually yield an equilibrium mixture that is about 70% ester. The experiment carried out did not use a one to one ratio and instead used 13 mmol of carboxylic acid to 11 mmol of alcohol. This was in an attempt to react all the alcohol and not limit it, but the reaction of 1-propanol and propionic acid produced a percent yield of 19.81%. The final product of ester after the drying work up was 0.253 g when the theoretical put the grams of 1-propyl propionate ester at 1.255 g. The final percent yield may be the result of an incomplete separation during the reflux between the water and organic layers. The reflux filled the side arm quickly and required the top layer to be dumped back into the round-bottom flask multiple times during the 15 min heating period. A higher ester yield may have been possible if the separation occurred at a slower rate so that the side arm did not fill so quickly, or if the side arm were larger. If the side arm were larger, it would allow for more catchment and a more defined layer to distinguish the organic from the water. The better distinction would also allow for only the organic layer to be removed after the 15 min reflux. Given that the reflux did not completely separate the organic product from the water, some of the ester may have been removed as the aqueous layer during the work up which would have lowered the final volume and therefore the percent yield. Still, the IR analysis confirmed the existence of an ester based on the peaks seen, so the esterification reaction between 1-propanol and propionic acid was successful in producing 1-propyl propionate.
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