1. 2.07 g of the mixture of naphthalene and benzoic acid was weighed accurately on a balance. The mixture was then dissolved in 40 ml dichloromethane and the solution was poured into a separatory funnel.
2. 20 ml of aqueous sodium bicarbonate solution was added to the dichloromethane. A stopper was placed on the separatory funnel and was shaken and pressure was frequently released. The 2 liquids separated into clear layers and the lower layer (dichloromethane layer) was tapped into an Erlenmeyer flask. The aqueous layer was placed into a 400 ml beaker. The dichloromethane was placed back in the separatory funnel.
3. The dichloromethane was extracted with 2 more fresh portions of sodium bicarbonate solution. The bicarbonate solutions are combined in the beaker.
4. The dichloromethane was dried with about 10g of anhydrous sodium sulphate for 10 minutes after which the sodium bicarbonate was filtered using the Büchner funnel. The mass of an evaporating dish was measured and the dichloromethane placed in the evaporating dish and placed on steam bath until it evaporated into a solid. The evaporating dish containing naphthalene was weighed to determine the yield.
5. A funnel was placed on the evaporating dish on the steam bath to collect some sublimating crystals which were used to determine the melting point.
6. The bicarbonate extract was acidified with concentrated HCl. A piece of litmus paper showed that it was acidic.
7. The benzoic acid was extracted by shaking it with25ml portions of dichloromethane. The organic extracts were collected in a pre-weighed Erlenmeyer flask and evaporated on the steam bath. The mass of Benzoic acid produced was determined.
RESULTS
(i) Naphthalene: 0.85g; Benzoic acid: 0.71g
(ii) The melting point of Naphthalene: 80-89º c
You May Also Find These Documents Helpful
-
2) Mix only the sodium bicarbonate and red phenol, and observe any changes that occur.…
- 776 Words
- 4 Pages
Good Essays -
In this experiment we also used a chemical method known as extraction. This process of separation is used when only one component of the mixture is soluble in a specific solvent. In our case we had to use hydrochloric acid (HCl).Extractions, is a way to separate a desired substance when it is mixed with others. The mixture is brought into contact with a solvent in which the substance of interest is soluble, but the other substances present are insoluble. And below is a…
- 854 Words
- 4 Pages
Good Essays -
The purpose of this lab was to produce benzoic acid by mixing sodium benzoate with hydrochloric acid. The Hydrochloric acid used in the experiment was a stock solution made by mixing HCl Acid and deionized water. HCl acid, historically called, muriatic acid or spirits of salt, hydrochloric acid is produced from sulfuric acid and common salt, NaCl (Princeton.edu). Since the early 1900 's, sodium benzoate has been used as a food preservative (SolarNavigator). It is utilized in a wide range of preservative applications due to its antimicrobial action combined with its low toxicity and low taste (SolarNavigator).…
- 931 Words
- 4 Pages
Better Essays -
During the reflux period, there have not been any signs of errors; the reflux distillation process occurred smoothly. Once reflux distillation was completed, the mixture was cooled to room temperature, then extracted thrice by a separatory funnel. Before any extractions proceeded though, the mixture already had two distinct layers – a top dark brown layer, and a bottom light yellow layer. This mixture was extracted with 9M sulfuric acid, and the aqueous layer, containing butanol, sulfuric acid, and water, was removed and discarded. The organic layer, consisting of the n-butyl bromide, went through a second extraction with water. This resulted in an organic layer of n-butyl bromide and water and an aqueous layer of water and a little amount of alcohol, which was discarded. The organic layer was then dried by extracting it with sodium bicarbonate; this is an extra step for drying the alkyl halide. The resulting organic layer contained the crude n-butyl bromide, and the drying procedure was completed by adding anhydrous calcium chloride until the solution turned clear. The drying agent was used to absorb any excess water and thus, resulted in a clear solution of n-butyl…
- 768 Words
- 4 Pages
Good Essays -
3) In order to extract the benzoic acid add 5.0 ml of the 1 mol NaOH solution, then shake the funnel 1 time per second and open it while it is upside down to allow the pressure out.…
- 858 Words
- 4 Pages
Better Essays -
Goggles were obtained and put on before entering the lab area. 2.0 grams of salicylic acid should be measured and placed into a 125 mL Erlenmeyer flask. 5.0 mL of acetic anhydride and 5 drops of 85% phosphoric acid was added to the Erlenmeyer flask. Drops of distilled water were added to rinse down bits of solids that were on inner wall of the flask. Mixture was heated on the hot plate for fifth-teen minutes, at 75 degrees Celsius. Two mL of distilled water was added 10 minutes into heating. Buchner funnel and filter were set up for the filtration…
- 1996 Words
- 8 Pages
Powerful Essays -
25 mL of sodium iodate solution was added to each flask. Using 10 mL and 25 mL graduated cylinders, the following volumes of CaCl2 solution with a concentration of 22 g/L was added to the Erlenmeyer flasks. In flask 1, 5 mL of CaCl2 solution was added. In flask 2, 15 mL of CaCl2 solution was added. In flask 3, 25 mL of CaCl2 solution was added. In flask 4, 35mL of CaCl2 solution was added. In flask 5, 40mL of CaCl2 was added. The mixture was stirred into each flask. The observations about the reaction in each flask was recorded in the Results and Analysis section. The filtration process was the same for each product. First, the suction filtration apparatus was set up. Using a Buchner funnel, the funnel was fit in a filter flask, which is an Erlenmeyer flask with a second opening off the side of its neck. The second opening was attached to an aspirator, which provided the vacuum. A circular piece of filter paper was placed over the holes in the bottom of the Buchner funnel. A heavy rubber tube was connected to the side arm opening on the filter flask. Then, the tube was attached to a special side opening on a water…
- 1092 Words
- 5 Pages
Good Essays -
a) To test for sodium bicarbonate we could use hydrochloric acid. The two form bubbles when mixed. These bubbles are carbon dioxide.…
- 557 Words
- 3 Pages
Good Essays -
The purposes of this experiment are to separate two components in a mixture, specifically sodium chloride and silica, and find the correlating percent composition of each.…
- 729 Words
- 3 Pages
Powerful Essays -
50mL of 0.1 M HCL was obtained in a beaker. A second buret was rinsed with water and then a small amount of HCL, and then filled with HCL. It was then labeled ACID. The initial volume was recorded and then approximately…
- 716 Words
- 3 Pages
Good Essays -
Experiment 55 consists of devising a separation and purification scheme for a three component mixture. The overall objective is to isolate in pure form two of the three compounds. This was done using extraction, solubility, crystallization and vacuum filtration. The experiment was carried out two times, both of which were successful.…
- 1426 Words
- 6 Pages
Good Essays -
Purpose: The purpose of this lab was to see how given amounts of sodium bicarbonate reacts with acetic acid and see how it creates different amounts of new compounds.…
- 486 Words
- 2 Pages
Good Essays -
Therefore, the experiment was performed to conduct quality control analysis on two commercial products to determine the amount of acid or base active in these two products and then compare the results to those of the manufacture. This was done through the preparation of standardized acid solution and standardized base solution, and through titration. The purpose of titration was to determine the concentration levels of the commercial products being used.…
- 1661 Words
- 7 Pages
Better Essays -
This exercise dealt with the melting points of pure mandelic acid and benzoic acid. The eutectic temperature and composition of mandelic and benzoic acid mixtures were determined. And finally, an unknown was identified by its mixtures and melting point.…
- 1111 Words
- 5 Pages
Better Essays -
A hot water bath was prepared in a fume hood using a 250-mL beaker. 2.5 g of p-acetamidobenzenesulfonyl chloride was placed into a 50 mL Erlenmeyer flask and 11 mL of dilute ammonium hydroxide solution was added to it. The mixture was stirred with a glass stirring rod. The mixture was heated in the hot water bath (70C) for 10 minutes and stirred occasionally. The flask was allowed to cool and placed in an ice water bath for 15 minutes. The p-acetamidobenzenesulfonamide was collected on a Buchner funnel and the flask was rinsed with about 10 mL of ice water. The sold was then transferred to a 25 mL round bottom flask and 5.3 mL of dilute hydrochloric acid was added along with a boiling stone. A reflux condenser was attached to the flask and the mixture was heated using a heating mantle until the solid had dissolved. The solution was then refluxed for an additional 5 minutes. Next, the mixture was allowed to cool to room temperature. Using a Pasteur pipet, the solution was transferred to a 100 mL beaker. While stirring with a glass rod, aqueous saturated sodium bicarbonate was added dropwise to the mixture. This was done until the pH measure between 4 and 6. The mixture was cooled in an ice water bath. The sulfanilamide was collected on a Buchner funnel and rinsed with 5 mL of cold water. The solid was air dried on the Buchner funnel using suction and then placed in a drawer to dry for a week. The next week the sulfanilamide was weighed and the melting point was measured.…
- 1387 Words
- 6 Pages
Better Essays