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.
25 ml of diluted unknown acid solution to 100ml beaker by using 25 volumetric pipet. 10ml of deionized water and 3 drops of phenlpthalin indicator the beaker labeled as 3. Potentiometric titration acid solutions 125 ml of NaOH was obtaining in a beaker and 50 ml of NaOH transfer to buret the tip and the meniscus is at below 0 ml. one magnetic stirring bar placed in a beaker contain one of the known solution on a stir. The pH recorded by using pH electrode before adding NaOH.
Fill the calorimeter cup approximately 2/3 with distilled water at room temperature and record the mass in Data Table 1 5. Measure the temperature of the tap water in the calorimeter cup and record in Data Table 2. 6. Carefully transfer the metal to the beaker with boiling water. Boil at least 10 minutes.
A stopper was placed on the flask while the mixture was stirring with stirrer for 11/2 hours. After the mixture had been stirred the flask was wrapped in foil and place inside the freezer overnight. After the mixture had been frozen overnight and thawed it was then filtered on a Buchner Funnel and the flask was rinsed with ethanol and recrystallized. To recrystallize, the crystals that were formed after being filtered were redissolved in about 500mL of warm ethanol because of the 4-Chlorobenzaldehyde used, and it was placed in an ice bath. After the crystals were formed they were filtered on a Buchner Funnel, they were let dry over night, and were weighed after they had dried.
I then allowed the remaining liquid to evaporate leaving behind salt. I poured the salt into the weighing dish and weighed the mass and calculated and recorded into table 1. Data Table 1: Experiment Data Grams Percent of Mixture Iron Fillings 0.9 gm 19.6 % Sand 1.4 gm 30.4 %
Transfer the extracts to a simple-distillation assembly and distill off all but 10 mLof the solvent on a steam bath. Save the recovered solvent. Evaporate the combined solutions to dryness on a steam bath or hot-water bath in a hood. To purify the crude product, dissolve it in about 5 mL of acetone by warming the mixture on a steam bath; add dropwise just enough mixed “hexanes” to turn the warmed solution faintly cloudy; then allow the solution to cool and allow the product to crystallize. Collect the green-tinged crystals on a small vacuum filter and wash them with a little mixed “hexanes.” The melting point of caffeine reported in the literature is 236°.
Next, cold water from the tap was collected in a plastic cup and measured in degrees Celsius. A handful of ice was then placed into the cup and sat for about 1 minute. The ice water was then stirred with the thermometer and the temperature was again collected in Celsius. Then the ice water sat for about 5 minutes and was stirred once again to collect the final temperature in Celsius. Once all of the temperatures were collected in degrees Celsius they were converted into degrees Fahrenheit and Kelvin.
Second, methyl benzoate is added to form a new carbon-carbon sigma bond. The intermediate magnesium alkoxide will then be hydrolyzed to form tertiary alcohol product. Experimental Procedure: Part A: Preparing the Grignard reagent • I placed 1.98 grams of magnesium turnings into a cleaned 250mL round-bottom flask and then attached the calcium chloride drying tube into the round-bottom flask • Then, I placed this flask onto a heating mantel and adjust the controller to setting ‘6’. This flask is heated until it was too hot to touch. • After the flask was heated, I removed it from the heating mantel and allowed it to cool to room temperature.
Nail polish remover contains the mixtures yellow dye, water, gelatin, fragrance, propylene carbonate and glycerol. So you have to do the heating by immersing a 25 Mk flask into the beaker with water filled into a hot plate. Experimental Procedures 1. First you have to set the distillation apparatus up. Use the ring stand & clamps to support the apparatus.
* 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.