The results from this experiment provide insight on organic substances and how to use microscale science. In Part A of this experiment, the accuracy of microscale experimentation was shown through the weighing of liquids and calculating density. The calculations performed to determine the densities of the liquids were accurate. The density of water was calculated to be .94g/mL and the density of hexane was calculated to be .6g/mL. A slight deviation was shown when the results were compared to literature values. On the other hand, Part B provided insight on organic substances and their properties of solubility. Each solute was shown to be soluble in at least one of the three different solvents. Benzophenone was soluble in methyl alcohol, but not in water. …show more content…
Malonic acid was soluble in water and methanol alcohol, but not in hexane. Biphenyl was soluble in hexane, but not in water. The reason why some of these solutes are soluble in only some of these solvents is due to polarity. For Part C of this experiment, a semi-microscale procedure was used. The results from this procedure determined the purity of sulfanilamide and propose that crystallization is a successful approach to purifying an impure substance. The results from Part D of this experiment provide the conclusion that when two immiscible liquids are placed in a vial, the organic solvent is the one that sets at the bottom while the inorganic solutes remain at the top of the vial. When dichloromethane and water are compared, dichloromethane is the organic solvent. When diethyl ether and water are compared, water is the organic solvent. When two solvents are compared, the solvent with the lower density is the inorganic
In experiment two, the drug Panacetin was separated by a series of chemical reactions into its three components: sucrose, aspirin, and an unknown active ingredient, either acetanilide or phenacetin. The purpose of this lab was to determine what percentages of each component is present in the pain-killer. The initial step was to dissolve Panacetin in dichloromethane. However, sucrose is insoluble in dichloromethane because organic molecules are soluble in organic solvents, and dichloromethane is an inorganic solvent, so only aspirin and the unknown dissolved. By using gravity filtration, sucrose was filtered from the solution and 0.30g of solid was collected.
Purpose: To learn about the international system of units (SI), to become familiar with common lab equipment and techniques, to gain proficiency in determining volume, mass, length, and temperature of a variety of items using common laboratory measurement devices, to learn to combine units to determine density and concentration, and to use laboratory equipment to create serial dilutions and determine the density and concentration of each dilution.
Procedure: Using distilled water, premeasured containers and objects determine displacement of fluids and density of objects. Use ice and heat measure temperatures in Celsius, Fahrenheit and Kelvin.
C. An unknown, rectangular substance measures 3.6 cm high, 4.21 cm long, and 1.17 cm wide.
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.
Purpose: The purpose of this laboratory was to gain an understanding of the differences between the freezing points of pure solvent to that of a solvent in a solution with a nonvolatile solute, and to compare the two.
Procedure: I used a ruler, thermometer, and scale to take measurements. I used a graduated cylinder, short step pipet, scale, and ruler to determine volume and density. I used a volumetric flask, graduated pipet, pipet bulb, scale, and glass beaker to determine concentrations and densities of various dilutions.
Abstract: One mixture of two unknown liquid compounds and one mixture of two unknown solid compounds were separated, isolated, purified, and characterized by boiling point. Two liquid unknowns were separated, isolated, and purified via simple distillation. Then, the process of an acid-base extraction and washing were used to separate two unknown compounds into two crude compounds: an organic acid and a neutral organic compound. Each crude compound was purified by recrystallization, resulting in a carboxylic acid (RCO2H) and a pure organic compound (RZ). The resulting mass of the pure carboxylic acid was 1.688g with a percent recovery of 31.80%, the boiling range was 244-245 °C, and its density was 2.0879g/mL. The resulting mass of the pure organic solid was 2.4902g with a percent recovery of 46.91%, the boiling range was 52.0-53.4°C, and its density was 1.5956 g/mL.
The objective of this experiment is to separate a 50:50 mixture of benzoic acid and benzil by using macroscale extraction. In the experiment, organic solvent diethyl ether is used. After adding 1.0 gram of the 50:50 mixture of benzoic acid and benzil to a 25ml Erlenmeyer flask, diethyl ether was added to the flask to dissolve the mixture. Benzoic acid and benzil dissolve in diethyl ether. Once the mixture dissolved in
Test tube 1 should have .04 g of benzophenone, test tube 2 should also have .04 g of benzophenone, etc., up to the fourth test tube.
In this experiment, 0.31 g (2.87 mmol) of 2-methylphenol was suspended in a 10 mL Erlenmeyer flask along with 1 mL of water and a stir bar. The flask was clamped onto a hotplate/stirrer and turned on so that the stir bar would turn freely. Based on the amount of 2-methylphenol, 0.957 mL (0.00287 mmol) NaOH was calculated and collected in a syringe. The NaOH was then added to the 2-methylphenol solution and allowed to mix completely. In another 10 mL Erlenmeyer flask, 0.34 g (2.92 mmol) of sodium chloroacetate was calculated based on the amount of 2-methylphenol and placed into the flask along with 1 mL of water. The sodium chloroacetate solution was mixed until dissolved. The sodium chloroacetate solution was poured into the 2-methylphenol and NaOH solution after it was fully dissolved using a microscale funnel.
14 mL of 9 M H2SO4 was added to the separatory funnel and the mixture was shaken. The layers were given a small amount of time to separate. The remaining n-butyl alcohol was extracted by the H2SO4 solution therefore, there was only one organic top layer. The lower aqueous layer was drained and discarded. 14 mL of H2O was added to the separatory funnel. A stopper was placed on the separatory funnel and it was shaken while being vented occasionally. The layers separated and the lower layer which contained the n-butyl bromide was drained into a smaller beaker. The aqueous layer was then discarded after ensuring that the correct layer had been saved by completing the "water drop test" (adding a drop of water to the drained liquid and if the water dissolves, it confirms that it is an aqueous layer). The alkyl halide was then returned to the separatory funnel. 14 mL of saturated aqeous sodium bicarbonate was added a little at a time while the separatory funnel was being swirled. A stopper was placed on the funnel and it was shaken for 1 minute while being vented frequently to relieve any pressure that was being produced. The lower alkyl halide layer was drained into a dry Erlenmeyer flask and 1.0 g of anhydrous calcium chloride was added to dry the solution. A stopper was placed on the Erlenmeyer flask and the contents were swirled until the liquid was clear. For the distillation
In the third stage of this experiment, the density of a liquid was determined and compared to known standards. A 100ml beaker was filled to about half-full with room-temperature distilled water. The temperature of the water in ◦C was recorded in order to compare to known standards later. A 50ml beaker was then weighed on a scale in order to determine mass and recorded. A sample of the distilled water with an exact volume of 10ml was then placed in the 50ml beaker using a volumetric pipette. The 50ml beaker with the 10ml of water was then weighed again and the initial mass of the beaker was subtracted from this mass to obtain the mass of the 10ml of water. With the volume and the mass of the water now known, density was calculated using d = m/V and recorded in g/ml. This process was then repeated to check for precision and compared to standard values to check for accuracy. Standard values were obtained from CRC Handbook, 88th Ed.
Samples of benzophenone, malonic acid, and biphenyl were each tested with water, methyl alcohol, and hexane. Benzophenone was insoluble in water as it is nonpolar while water is highly polar. Benzophenone was soluble in methyl alcohol, dissolving in 15 seconds, because methyl alcohol is intermediately polar as benzophenone is nonpolar. Methyl alcohol is polar but not as much as water. Thus, the nonpolar benzophenone was soluble in methyl alcohol. Benzophenone was partially soluble in hexane because hexane is nonpolar as is benzophenone. Thus, benzophenone was dissolved in hexane. Malonic acid was soluble in water because both malonic acid and water are polar. It took 25 seconds for malonic acid to dissolve in water. Malonic acid was soluble in methyl alcohol because malonic acid is polar and methyl alcohol is intermediately polar, allowing malonic acid to dissolve in the methanol in 15 seconds. Malonic acid was insoluble in hexane because hexane is nonpolar while malonic acid is polar. Biphenyl was insoluble in water as water is highly polar whilst biphenyl is nonpolar. Biphenyl was partially soluble in methanol which is intermediately polar whilst biphenyl is nonpolar, allowing it to dissolve a little. Biphenyl was soluble in hexane because both biphenyl and hexane are nonpolar molecules. Biphenyl dissolved in hexane in 10 seconds.
For the first lab, students worked individually to purify vanillin, but worked in pairs in order to purify an unknown. We began the process of purifying vanillin by weighing it out and dissolved in water, afterwards we placed the solution in an ice bath. After a minutes, we vacuumed out the vanillin, in order to obtain the crystals. In general, recrystallization is used to purify compounds—which was the purpose of this la . As for the unknown solid, a similar process was conducted. However, for the unknown, students had to determine the right solvent in which the unknown would dissolve in and be used for the