8. Placed the remaining mixture, containing sand, benzoic acid and table salt into beaker and added 50mL of distilled water. 9. Set up the beaker stand and burner fuel and heated the beaker of solids and water to near boiling. Stirred the mixture to make sure all soluble material dissolves.
The mixture was decanted again in to the same beaker. Next, we added boiling chips to the liquid and evaporated the solvent over the hot plates under the hood. After the solvent was evaporated and the flask was cooled, we used a spatula to remove a small amount of the crude product and took its melting point. We determined the melting point range of the sample to be 43.0-46.0 degrees Celcius.The crude product was yellow colored when it was warm and orange in color when cooled and sticky. We then recrystallized our sample using 5 ml of warm acetone that was heated on a hot plate under a hood.
Then place the water in the 25ml beaker for the heating bath and lower the set-up so that when the 25ml round bottom flask is immersed the beaker is about 2/3 full. 5. When that is finish, using the highest setting on the hot plate heat the water until it is nearly boiling. Then turn the heating bath off. 6.
Stir very slowly with a stirring rod and record the highest temperature reached by the water in Data Table 2. 10. Remove the calorimeter lid, retrieve and dry the metal. Return metal to its original place. Pour the water down the sing.
Hydrochloric acid was then added to the solution until the bubbles stopped in order to completely get rid of all of the zinc. Next, we used vacuum filtration to filter the copper out of the solution. We drizzled alcohol and acetone over the copper to help it dry faster. Once it appeared dry, we weighed the copper and filter paper. When we subtracted the mass of the filter paper, the mass came out to 1.312g.
Gently stir the pellets until the acid is dissolved by shaking the the apparatus. Lift the calorimeter lid and wash out its contents and the thermometer. Repeat this experiment using 50.0 mL of 1.0M acetic acid. Repeat experiment using 25.0 mL of each 2.0M sodium hydroxide and 2.0M acetic acid. Data Table(s): Reaction equation Mass of solid NaOH Initial Temp.
Extraction and Drying: Using a separatory funnel, the cooled filtrate was extracted with 10ml of methylene chloride. After shaking our mixture, we broke and dried our emulsion by slowing passing the lower layer through a cotton ball layered with anhydrous magnesium sulfate. The extraction process was repeated 2 more times for maximum collection of the organic layer. Distillation: The extracts were poured into a 50ml round bottle flask and connected to a simple distillation apparatus. To obtain the caffeine, the methylene chloride was removed from the extract, leaving us with our solid caffeine residue.
2. Obtain a clean and dry crucible and lid. Crucibles very slowly adsorb small amounts of water vapour from the atmosphere and must be heated for a minute or two to get rid of adsorbed water molecules before you can get an accurate “initial mass” for a crucible. Crucibles are usually heated in clay triangles, which in turn are set on top of rings attached to ring stands. 3.
* Pour a little ether over the nutmeg residue on the filter paper so that any Diethyl ethanol traces clinging to it is washed down and mixed with the filtered liquid underneath. * Filter the mixture by gravity filtration, washing the nutmeg residue with 10ml of diethyl ether. Evaporate the Ether from the filtrate * Recrystallize the product from ethanol. Filter using a Buchner funnel and wash them with cold water as shown in the diagram (see figure 2). * Let the crystals dry for one week, record the weight and take a sample and put into a glass capillary tube to obtain a melting point using the Melt-Temp machine.
If contact occurs, wash the contacted area immediately with cool water. Add 2 drops of acetone to tube 1,2 drops of butyraldehyde to tube 2, 2 drops of flavoring agent to tube 3, 2 drops of your unknown to tube 4. Mix well by agitationand noth the almost instantaneous formation of precipitate in tubes 1 and 2. Record all your observations for samples in table 20.1. B. Tollens Reagent.