To Separate the Components of Panacetin

I.  Introduction

        The purpose of this experiment is to separate the components of panacetin. We need to find out if the composition of panacetin is as stated on the label accurate. We will also identify the unknown components in panacetin.

II. Experimental Procedure

• In this experiment dichloromethane may be harmful if ingested, inhaled, or absorbed through the skin. There is also a chance the inhaling this chemical can have a prolonged effect of the human body which dichloromethane may cause you cancer. The way you can minimize is this by having less contact with the liquid and don’t breathe in the vapor.

1. Separation of Sucrose

1. Accurately weigh about 3.00 grams of panacetin and transfer it to a clean, dry 125 mL Erlenmeyer flask
2. Add 50 mL of dichloromethane to the flask.
3. Stir the mixture thoroughly with a glass stirring rod to dissolve as much solid as possible and  use the rod to break apart any lumps or granules
4. Use a preweighted fluted filter paper and filter the mixture by gravity into a small flask saving the filtrate for the next step
5. Set the filter paper aside, being careful not to lose any of the sucrose, and reweigh it when it is completely dry.
6. Record the mass of the sucrose in your notebook
7. If requested, submit the sucrose to your instructor in a tared (preweighted) and labeled vial

1. Separation of Aspirin

1. Transfer the filtered to a separatory funnel and extract it with two separate 30 mL portions of 5% sodium bircarbonate
2. For each extraction, use a stirring rod to stir the liquid layers until any fizzing subsides before you stopper and shake the separatory funnel
3. Dichloromethane layer will be at the bottom, you will have to transfer each layer to a different container labeled and return the dichloromethane layer to the separatory funnel before the second extraction
4. Combine the two aqueous extracts in the same container and save the dichloromethane layer for the following step (isolating of the unknown component)
5. Slowly add 7mL of 6M hydrochloric to the combined aqueous extracts while stirring with a glass rod
6. Test the pH of the solution as described in experiment 1 and add more acid, if necessary bring the pH of the solution down to 2 or lower
7. Cool the mixture in an ice/water bath for at least for 10 min and collect the aspirin by vacuum filtration, and wash it on the filter with cold water
8. Let aspirin dry on the filter for a few min with the aspirator running, then dry it to a constant mass
9. Weigh the aspirin and record its mass in your lab notebook

1. Isolation of the unknown component

1. Use a filter flask attached to a trap and aspirator to evaporate the solvent from the dichloromethane solution
2. Heating and swirling the solution over a steam bath or in a hot-water bath will increase the evaporation rate
3. Discontinue evaporation when only a solid residue remains in the flask or when no more solvents evaporate
4. Transfer the unknown components to a tared vial and let it dry to a constant mass
5. Weigh it before you begin experiment 3
6. Calculate your percent recovery; calculate the approximate percent composition of panacetin based on the total mass of components recovered