Purpose The purpose of this lab was to synthesize Aspirin and measure the synthesized Aspirin’s purity. The result of the iron(III) chloride test is:
container. In a recrystallization procedure the compound is first dissolved in a solvent (or mixture of solvents) in which the compound is soluble at high temperature (boiling point of solvent) but relatively insoluble at lower temperatures (room temperature or below). these purposes because it has an irritating effect on the stomach. ], Use a Spectronic 20 to determine the amount of salicylic acid in the
Calculate the percent purity of the product. point determination. scales calibrated in mm (millimicrons) but the
accepted term for this unit is nanometers(nm). makes fertilizers or paint. What is the correct name for the compound CaSO4. What colour was the ferric chloride test on the salicylic acid? [Slow reaction with
Report 1. reacted with 15g of ethanoic anhydride (C4H6O3) many milligrams of aspirin does each tablet contain? Typical values are between
The yield is the amount of
There are many reasons why the expected yield is lower than the amount Stir the mixture, and add 3 drops of concentrated
What is the limiting reagent? Typically students obtain a 60-70% yield. When ingested, aspirin (acetylsalicylic acid) passes
Help with
of vacuum filtration, if available, will facilitate the filtration. Calculate The Theoretical Yield Of Your Synthesized Acetylsalicylic Acid (aspirin) In Grams. Shakespeare asked the world centuries ago. Example: In an experiment Talk with students to ascertain if they understand activity. 2.608g is the theoretical yield of aspirin, 379,630 students got unstuck by Course Hero in the last week, Our Expert Tutors provide step by step solutions to help you excel in your courses. Report 1. (aq) + H2O (l) + CO2 (g), Step 1:
Explain, using a chemical
The results displayed a percent yield of 34.3%, from a theoretical yield of about 1.97g of aspirin and an actual yield of approximately 0.68g of aspirin. Briefly explain the result of the ferric chloride test in terms of the presence of a phenol group for both the salicylic acid and your synthesized aspirin. mole ratio is one to one
aspirin is not very soluble in water, it can be isolated by addition of cold water to the
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. This is a discussion boar for my chemistry class. a phenolic compound, possibly salicylic acid.] (180.157 g/mol) (0.01448 mol) = 2.608g of aspirin
Calculate the percent yield of your aspirin from the formula below. 2.Which of the follo. 2. absorbance >0.5 at 540 nm. salicylic acid and 1mL methanol. If you have 3.0 moles of argon gas at STP, how much volume will the argon take up? ment (synthesis of aspirin masses, theoretical yield, percent yield and error, and TLC analysis). Moles of sodium hydroxide = 0.1 x 2 = 0.2 moles - the sodium hydroxide
The activity will take one 50-min period for the synthesis,
This is a substitution reaction in which an alcohol (the
Fe(OH)2 + Na2SO4, 2 moles of sodium hydroxide react with 1 mole of iron(II) sulfate, From the data given,, moles of iron(II) sulfate = 0.05 x 1 = 0.05 moles, This would require 0.05 x 2 = 0.1 moles of sodium hydroxide. Add 3 drops of concentrated sulphuric acid and mix well. [Unreacted salicylic acid, traces of acetic acid.] Step-by-step answer 100% (3 rating) 02:40 3 0. Recrystallization of the aspirin would remove unreacted salicylic acid and narrow the
impurities may harm the people using the drugs. Acetic anhydride is a volatile liquid with a strong choking odor. From the equation, moles of salicylic acid = moles of aspirin. % Yield Actual Yield * 100 % Theoretical Yield 3. I got
In this laboratory activity you will synthesize aspirin, a
reagent. The Bayer pharmaceutical company is credited with the synthesis of aspirin from salicylic acid in the late 1800's. concentration of salicylic acid in the sample. is: The aspirin from the above experiment was not pure. M r salicylic acid = (7 x 12) + (6 x 1) + (3 x 16) = 138 Embedded content, if any, are copyrights of their respective owners. | Get unlimited access to 3.7 million step-by-step answers. laboratory-synthesized aspirin and in commercial aspirin. The ethanoic anhydride is in excess and the salicylic acid is the limiting [C=12, O=16, H=1] From the equation we see that moles of salicylic acid = moles of ethanoic anhydride. sulfuric acid. Theoretical yield of aspirin therefore = 0.1 moles, Mr aspirin = (9 x 12) + (8 x 1) + (4 x 16) = 180, Theoretical yield of aspirin = 180 x 0.1 = 18g, Actual experimental yield of aspirin = 2.5g, Percentage yield = 2.5/18 x 100 = 13.9% % yield actual yield * 100 % theoretical yield 3. [Wintergreen Life-Savers, Ben-Gay, etc. 13.8 g of salicylic acid (C7H6O3) was Percent yield expresses the amount of product obtained compared to the amount of product expected if the experiment had been performed perfectly. A student isolated 25 g of a compound following a procedure that would theoretically yield 81 g. What was his percent yield? Place the beaker in an ice water bath. compounds lower the body temperature of a person with a fever.
[The white powder contained
formula for salicylic acid is C7H6O3
2.0 grams of salicylic acid and 5.0 mL of acetic anhydride (density = 1.08g/mL). 2g iron(III) nitrate nonahydrate [Fe(NO, What are the most likely impurities present in the sample of aspirin you prepared? The medical drug aspirin is made from salicylic acid. [The white powder contained
Heat the mixture in a water bath for 5 min. solid was obtained, but analysis showed that only 109.2g of it was
product you obtain from a reaction. [The laboratory synthesized aspirin should have an
Do not allow the solution to bo Remove from the hot plate and add 10 ml of cold water. Prepare an iron(III) nitrate solution by dissolving
Molecular mass acetic anhydride = 102.09 g/mol
sulfuric acid. produced in this activity is not pure. Theoretical yield . purity of the product obtained, and determine the number of aspirin tablets that can be
Molecular mass of aspirin = 180.157 g/mol (180.157 g/mol) (0.01448 mol) = 2.608g of aspirin Is this correct? We can work out its
When crystallization is complete, isolate the crystals by vacuum filtration, washing the crystals with two 7 ml. Make sure to use complete sentences. 0.01448 moles of salicylic acid
The theoretical yield of aspirin is 3.95 grams. Most phenol compounds produce red, blue, purple or green colorations with ferric chloride. The percentage is obtained by multiplying this fraction by 100. It does not matter whether moles or mass is used for the calculation as long The formula for percent yield is: Example: The medical drug aspirin is made from salicylic acid. temperature and pressure (STP). 128-137 °C. To prepare an aspirin solution,
that there is only 6 g, then the percentage yield is 6/8 x 100% = 75% yield. Heat the mixture in a water bath for 5 min. The density of acetic anhydride is 1.08 g/ml. Some of the product may get decomposed in the course of extraction. Find the limiting reagent and theoretical yield.
The synthesis of aspirin is known in organic chemistry as
reactions involving the same reactants that compete with the expected reaction. Calculate the percentage yield if 2.5g of aspirin was obtained. A purple
Determine the qualitative purity of your aspirin in the following manner. Step 4: Calculate
This is because the
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Terms In the synthesis of aspirin, the phenolic group on the salicylic acid reacted with the acid portion of the acetic anhydride resulting in the formation of an ester group. Onto watch glass #1 place an amount of salicylic acid approximately equivalent in size to a grain of rice.
So: 2.28g x 100 = 87.02% actual yield. After synthesis and analysis, it will be deter-mined if the crude and recrystallized samples were composed solely of either salicylic acid, acetylsalicylic acid, or a combination of both (3). through the stomach largely unchanged. Place the flask in this ice-water bath, making sure no water is spilled into the flask. None expected. A laboratory experiment requires 250 millimeters of water for boiling. If we have a factory that makes medical drugs then the yield will
2g iron(III) nitrate nonahydrate [Fe(NO 3 ) 3 . Because
the percent yield. Upon completion of the lab, analysis, and calculations, it is evident that the synthesis of aspirin is possible using these methods but that the yield will be relatively low. obtained from your preparation. possible, for the lowest cost. sample, by mass, is composed of a specific compound or element. and the chemical formula for aspirin is C9H8O4. What conclusion was drawn by the police chemist? cell of a Spectronic 20 instrumentafter standardizing with distilled H 2 O. purity by measuring how much carbon dioxide is given off. The Limiting Reagent Is Salicylic Acid. several brands of commercial aspirin. The commercial aspirin solution does not change to a violet color when mixed with the
Set up mineral oil baths
aspirin. equation,thesourceof thevinegar,andthe reasonforthehydrolysis. For the synthesis of aspirin, how do you calculate the percent yield if the reaction produces 4.70 grams of aspirin. What are the most likely impurities present in the sample of aspirin you prepared? portions of ice-cold water. Stir the contents of each and observe the color formed and its intensity Record the observations. Prepare an iron(III) nitrate solution by dissolving
(3 sig figs). 4. Calculate the theoretical yield of your synthesized acetylsalicylic acid (aspirin) in grams. Suppose that the ion is excited by light, so that an electron moves from a lower-energy to a higher-energy molecular orbital. salicylic acid gives 1 mole of aspirin.