Swirled the beaker to dissolve as much of the solid as possible, then placed the beaker on the hot plate until the solid completely dissolved. 400 mL Beaker (2)
The sulfuric acid was a clear solution with a strong odour when heated. Inaccurate calibrations of the hot plate or balance could have shown higher or lower quantitative data which would have affected the results by producing either a higher or lower percent yield. on. The active metabolite ingredient in acetylsalicylic acid (aspirin) is salicylic acid (Wikipedia, Salicylic acid, 2013), which was first discovered by Edward Stone in 1763 (Wikipedia, Aspirin, 2013). After the liquid drained through the filter paper, washed the filtrate with two 10 mL portions of cold distilled water. can use them for free to gain inspiration and new creative ideas for their writing assignments. The aspirin will be prepared by reacting a weighed sample of salicylic acid with a weighed sample of acetic anhydride. Section III – Calculations: show your calculations for moles of salicylic acid and acetic anhydride; theoretical moles yield of aspirin; theoretical mass yield of aspirin; and percent yield of aspirin. 12.
Using a clean, dry 150 mL beaker, dissolve the aspirin in about 1mL of 95% ethyl alcohol, and warm the mixture slightly by placing it in the hot water bath.
The findings showed that acetylsalicylic acid can be produced through a reaction between salicylic acid and acetic anhydride, but that a much lower yield will be produced. Since both acetic anhydride and salicylic acid have a coefficient of 1, the smaller number is the limiting reactant. First, convert both masses to moles. 107g In this experiment, you will prepare aspirin from salicylic acid and acetic anhydride using sulfuric acid as a catalyst. Purify the rest of the aspirin by recrystallization.
Assemble a Büchner funnel and filter flask as shown in the figure.
125 mL Erlenmeyer Flask (1) Remove the flask from the water bath and slowly add ten drops of deionized water to convert any excess acetic anhydride to acetic acid. 0°C As for what else could be in the test tube, either unreacted reagents (salicylic acid? Do radioactive elements cause water to heat up? 2.Sometimes when you open an old bottle of aspirin you can detect a "vinegar-like" smell. C2 - Using the limiting reagent calculate the maximum theoretical yield for your reaction. Aspirin has many real-life applications. Describe One Safety Practice Important To This Lab Experiment; Explain You Answer Specific To The Chemistry And Procedures Used In This Lab. A way to get rid of the source of error would be to keep the samples in a more isolated area where there is a smaller chance of contamination. Be aware that using too much water or warm water in this step may affect your results. Recorded the weight on the data table. If crystals do not appear scratch the walls of the flask with a stirring rod to induce crystallization. The boiling chips (calcium carbonate) were white, opaque crystals. Why the polls were wrong about Trump (again), 'Stop the count': Trump backers rally at vote centers, Live: Biden moves closer to reaching 270 votes, Union members picked Biden after Trump 'abandoned' them, Fox News hosts question network's Ariz. call for Biden, Black men drifted from Dems to Trump in record numbers, Falcons player is brutally honest after not being traded, Pennsylvania AG on Trump lawsuit: 'We'll win again', Trump campaign unleashes wave of suits in key states, Giants trainer may have saved this player's wife's life, Democrats disappoint in House and Senate races. Either concentrated sulfuric or phosphoric acid may be used. Theoretical yield 1 mole is equal to the molar mass of a substance; therefore, the grams of acetic anhydride and grams of salicylic acid must be divided by their molar masses respectively. Sample Calculations . This is just a sample.
Add approximately 2.0 g of salicylic acid to the flask and weigh it again. In this reaction, the –OH on the salicylic acid acts as the alcohol and the acetic anhydride acts like a carboxylic acid. Substituting Lewis structures for molecular formulas in chemical reactions provides more information. https://phdessay.com/synthesis-of-aspirin/, Synthesis of Cinnamaldehyde from Benzaldehyde. Q2: If 0.150 moles of salicylic acid and excess acetic acid are used during a synthesis of aspirin, how many grams of aspirin will be obtained if the reaction gives a 38% yield? Salicylic Acid: purple. ), ____________ Mass of flask with stopper + salicylic acid, ____________ Mass of flask with stopper + salicylic acid + acetic anhydride, Identify the limiting reactant __________________________________, ____________ Calculate the theoretical moles of aspirin, ____________ Calculate the theoretical mass of aspirin in grams, ____________ Mass of filter paper (Büchner funnel, after recrystallization), ____________ Experimental mass of aspirin in grams, ____________ percent yield of aspirin = experimental mass of aspirin x 100 / theoretical mass of aspirin, ____________ Experimental melting point of aspirin, ____________ Literature melting point of aspirin (you must look this up with CRC or online). 1. Measured out 5 mL of ethanol from the fume hood in a graduated cylinder, and added it to the 100 mL beaker containing the solid aspirin. When the salicylic acid and acetic anhydride were mixed, a white, powdery solution formed. It is necessary to consider resonance forms of intermediate structures. Allow it to dry on the filter paper until the next lab period. Weighed out 1.5g of salicylic acid on a piece of filter paper. 5. 1.51g C7H6O3 x 1 mole C7H6O3 x 1 mole C9H8O4 x 180.154 g C9H8O4 138.118 g C7H6O3 1 mol C7H6O31 mol C9H8O4 58. Gas building in a sealed container is the primary cause of laboratory explosions and heating the beaker to high or not providing sufficient space around the Erlenmeyer flask may produce an explosion.
2. Aspirin is an organic ester.
Percent yield = Actual yield x 100 = l 0.676g l x 100 = 34.3% 10. A contamination of the substances used or the glassware could have caused the substances to react differently with each other, again causing the percent yield to change depending on how the contamination affected the substances by producing a higher or lower percent yield. Were the new crystals the same substance as the old ones? Clamp the stoppered Erlenmeyer flask to a ring stand to hold it in the 70-80˚ C water bath. This reaction is the reverse of the synthesis reaction. Let Professional Writer Help You, 6000 Fairview Road, SouthPark Towers, Suite 1200, Charlotte, NC 28210, USA. Compare the literature melting point and infrared spectrum to the experimental and comment on the purity of your aspirin.