Lab 3 post-lab PDF

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Lab 3 post-lab...

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Solid Liquid Extraction-Isolation of Trimyristin from Nutmeg Post Lab Results and Calculations: Initial mass of nutmeg: 4.506 g Volume of Methylene Chloride used to extract nutmeg sample: 45.0 mL Temperature of the first drop of methylene chloride captured in receiving flask: N/A (used rotary evaporator) Final weight of the extracted/isolated trimyristin product: 0.323 g Melting point range of the recovered trimyristin product: 55.6-57.3 ℃

Percent Recovery Calculation: (mass of recovered product/mass of nutmeg)*100 = percent recovery (0.323 g / 4.506 g)*100 = 7.17% 0.25*4.506 g = 1.13 g of trimyrsitin Percent Yield Calculation: [mass of recovered product/(% composition of trimyristin*mass of nutmeg)]*100 = percent yield (0.323 g / (0.25*4.506 g)]*100 = 28.7% Discussion/Conclusion: Throughout this lab we performed reflux, gravity filtration, simple distillation, and vacuum filtration in order to obtain our final product of trimyristin with a 28.7 % percent yield. Because the expected recovery for our specific mass of nutmeg was expected to be about 25% trimyristin (1.13g), our small percent recovery of 7.17% is off by about 13%. The small percent recovery is still reasonable due to sources of error throughout the lab. When the purified crystals of trimyristin were transferred from the Büchner funnel to the watch glass before being weighed, some of the product spilled onto the lab bench and were therefore not included in the final weight of the extracted trimyristin product. Therefore, this had effect on the percent recovery of

trimyristin, which should have been around 25%, because some of the recovered product was lost after filtration due to human error. Another source of error include that we may not have gotten all of the solution out of the round bottom flask when rinsing it with acetone prior to using suction filtration to isolate and dry the crystals. This would then cause us to have a fewer amount of crystals in the end since some of the solution was left behind causing a lower percent recovery. After isolating and drying the final product of trimyristin using suction filtration, a maltemp apparatus was used to determine the melting point of the substance. The melting point range of the trimyristin product recovered in this lab was 55.6-57.3 ℃ , which is very close to the melting point range of trimyristin, 56-58℃ . Because the melting point of the recovered product is within the range of trimyristin, we can conclude that our final product did not have many impurities present. If there were impurities, the melting point range of our final product would have been much lower and more broad than the resulting melting point range that we found our product to have. Therefore, the final product was mostly purified trimyristin with hardly any impurities....