Extraction and Evaporation. Separating the Components of Panacetin.
Pre-Lab: Analgesic drugs are known for reducing pain, while antiseptic drugs reduce symptoms such as fevers and swelling. However, some of these drugs can reduce both illnesses. To obtain a pure compound in these drugs, the scientist needs to separate the desired compound by taking advantage of the different physical and chemical properties. Such as; different boiling points, melting points and their solubility properties. To do this a chemist can also asses the differences between acidic and basic substances when they are added to water soluble mixtures. Within this current experiment I will asses the pharmaceutical preparation of Panacetin, by using it's solubility along with other organic molecules. We know that Panacetin is made up of sucrose, aspirin and some other unknown substance. We know the substance has to be Phenacetin or Acetanilide. To help solidify our reasoning, we need a % recovery of 8-12% sucrose, 35-45% aspirin and 45-55% unknown. Sucrose for example is insoluble in dichloromethane, while aspirin is soluble in CH2Cl2, but not in H2O. The organic compound sodium hydroxide will convert aspirin to Sodium Acetylsalicylate, which is soluble in water. Phenacetin and Actinilide are soluble in CH2Cl2, but not water. Actinilide and Phenacetin can be converted to salts by Sodium Hydroxide. The drawn out calculations on the last page will show this process being completed. Phenacetin and Acetinilide being broken down into salts helps us express that, Panacetin and dichloromethane should dissolve the aspirin and our unknown substance, but leave our sucrose behind that can be extracted by filtration. Aspirin can then be dissolved by an aqueous solution, HCL and dichloromethane. Which will then be converted to a salt. Once we dissolve the salt, our unknown solution will be left behind. The drawn out calculations on the last page of the lab will also show all the organic molecule's, molecular structures.
Problem: Is the composition of Panacetin as stated on the label correct?
Hypothesis: I believe that the label is correct. Because our bodies have the ability to use Acetaminophen, to convert Acetanilide and Phenacetin. Without that ability or bodies would have shown us bad symptoms, as soon as we consumed Panacetin.
Accurately weigh 3g of Panacetin, put in 125ml beaker
Add 50ml of CH2Cl2 to 125ml beaker
Stir mixture until its dissolved, use an already weighed filter paper to filter the mix using gravity. Weigh sucrose after it dries and try to retain as much as possible!!! Aspirin Separation
Transfer to funnel and extract by using two, 25ml portions of aqueous 1M Sodium Hydroxide. You will need to separate containers and label each. Then return the dichloromethane to separate funnel before next extraction Combine the 2 aqueous extracts into the same container and save the dichloromethane layer. Add 10mlof 6M HCL SLOWLY, while stirring to the combined aqueous extracts Test the Ph level and add more acid if needed to reach a Ph of 2 Cool with ice bath until the solution is at least 10 degrees centigrade, and the use a vacuum to filtrate Unknown Separation
Use filter flask attached to a trap and aspirator to evaporate the solvent (CH2Cl2) Stop when the solid is the only thing remaining, or when no more evaporation is occurring
Observation: During the first portion we were able to weigh exactly 3.00g of Panacetin. Once I added CH2Cl2, I saw the white solution become a milky, or light colored gray liquid form. As we stirred the Panacetin dissolved slowly, and the fog like substance remained. After the filtrate was separated from the solution, I was left with a white, powdery substance called sucrose. We set the damp sucrose aside and 24hrs later, we took its mass. Later on during the aspirin...
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