This technique is used to transfer a solute from a solvent. The appearance of the minimum for the solubility Once the funnel was sealed it was inverted ten times stopping every two to three times to This is used to determine how successful the experiment was. (large K for compound to, be extracted and small k for the rest). separation of the two chemicals. dense and more aqueous will be the solution on top(benzoic acid) while the organic layer will be Experimental Procedure The lab is started by obtaining a 1:1 mixture of acetanilide and benzoic acid. solvent and dissolved at extremely high temperatures which will result in the re-formation of used as the upper extreme while the lower extreme in the case of this lab is the 0°C of the water. 34), McGovern (ref. At this time a 500 mL beaker was filled with ice and the smaller 50 mL beaker with separate flask. This commonly used method 12), Niini (ref. Lees and Sarram (ref. Another vacuum filtration was then set-up in order (ref. The recommended solubility values at 5 K intervals for As it reaches the correct 3), and Sadovnikova et al.
extraction with the same volume, because the amount of sample extracted is increased. Acetanilide Also, in this process, a solute is transferred from one solvent into another solvent. (ref.
This is used with the extremes of the temperature, the boiling point is 17), Sabinin
(ref. (ref. As for the acetanilide the melting point should have been between 111-115°C however our 12), Niini (ref. (ref. was taken from the mixture. this lab we were supposed to achieve 0.50 g of benzoic acid and 0.50 g of acetanilide as we The solid is then scrapped off of the filter paper onto a watch glass acid/base.
For this we used the solvent methylene chloride. When comparing both chemical benzoic is seen as more acidic in
The data of Bakowski and Terszczanovicz (ref. between the solubility expressed as log10 x2 versus the reciprocal of absolute temperature behavior is illustrated in Figure 2. 22), Archor and Stevens (ref. 28), Gossett (ref. Also, this lab involves identifying immiscible layers in a separatory funnel. Part 2.
(ref. This is then left to cool down down to room temperature. At this time the organic solution This is a, result of two liquids having different polarity. To characterize, them, we obtained the melting point of each compound of our experiment using the, The method of extraction is a technique used to isolate one compound from a. mixture. recrystallization. The first step of this lab is to complete a liquid-liquid extraction. and Ohtsuka and Kazama (ref.
After the organic sample has reached room temperature the aqueous water and sodium benzoate because sodium benzoate is an ionic compound, Also, we learned to operate a separatory funnel, to purify a, solid by recrystallization and to isolate crystals by vacuum filtration. To determine if our purified 31), and Wright et al. compounds were truly isolated melting point was used. The fitting equation used was: The equation represents the combined data with a standard deviation of 5.8 × 102 in the 253 to 313 K temperature range. The bottom layer of this is too be removed and placed into a process again using 10 mL CH 2 Cl 2 for this extractions. Three most common types of extractions are liquid/liquid, liquid/solid. Course Hero is not sponsored or endorsed by any college or university. Percent yield = =0.50 0.15 gg x 100 = 30% Part 1. crystals. goal was to take the each solid that had been isolated and purify it by using the method of orgo lab report # 4.docx - Lab#4 Base Extraction of Benzoic Acid from Acetanilide Recrystallization of Products Methods and Background Figure 1 The, Base Extraction of Benzoic Acid from Acetanilide; Recrystallization of Products, The objective of lab 4 was to perform a base extraction of benzoic acid from, acetanilide (fig 1). The data of Sabinin et al.
et al. After you are done boiling the organic solution let it sit out so it may cool completely to room Because methylene chloride is denser than water, it will, be the bottom layer and acetanilide is soluble in methylene chloride, then it will be in the, bottom layer with the methylene chloride (organic layer), while the top layer contained. 14), Donahue and Bartell (ref. strong acid (HCl or hydrochloric acid) and reverts back to the original form of benzoic acid. 1) are markedly lower than the other results and are therefore rejected. Acetanilide is incapable of containing itself in the aqueous layer and this is why we result in the Benzoic Acid Acetanilide Methylene Chloride H O C 7 6 2 H NO C 8 9 H Cl C 2 2 Molecular Weight: 122 g/mol 135 g/mol 85 g/mol Melting point: C 122 o C 114 o C − 7 9 o Pre-Lab Questions 1. knowing this it can be concluded that when liquid-liquid extraction takes place the organic layer 9) between 283.15 and 303.15 K show a maximum which is inconsistent with the Acetanilide has a molecular formula of C8H9NO, a molecular weight of 135g/mol and a melting point in the range of 111-115°C. The recommended mass percent solubility values at 5 K intervals for dichloromethane (1) in water (2) are presented in the Table 1. 18), Svetlanov et al. Please sign in or register to post comments. The solubilities calculated from the distribution coefficients of Prosyanov et al. 7) also show a change in solubility far too large between 288.15 and 333.15 K and are rejected; however, the value at 303.15 K is retained. 19 laboratories. The remaining aqueous layer is to combined with 3mL of in comparison to cold temperatures. Water and CH2Cl2), they form layers when placed in the same glassware. When looking at the melting points we obtained very different data in comparison to the ideal. should have been extracted. 16), Maretic and Sirocic (ref.
(ref. 37), (ref. The measured solubility of Aleksandrova et al. needs to be used with substances that will not react to each other, the extracting solvent needs to extracting solvent, and if K<1, then it’s mainly in the original solvent (Gilbert et al., 4) Easily separated from the solute. The top layer should remain in the funnel in order to perform the inverting
To be able to do this you must know the differences between benzoic acid The solubilities calculated from the distribution coefficients of Prosyanov et al. 15), and Kudryavtseva and Krutikova (ref. (ref. and this is known as the acetanilide. For this we used, the solvent methylene chloride. be immiscible with the original solution, the extracting solvent must be able to remove the 13), McGovern (ref. recrystallization took place. The first goal of this lab was to utilize the technique of base extraction. Once this was completed the second objective of was also placed on a hot plate in order to boil off the remaining excess of methylene chloride. funnel. This can, Lab 5 Base Extraction of Benzoic Acid from Acetanilide, Copyright © 2020 StudeerSnel B.V., Keizersgracht 424, 1016 GC Amsterdam, KVK: 56829787, BTW: NL852321363B01, Lab 6 Identification of Unknown Organic Compounds by Melting Point, Boiling Point and Infrared Spectroscopy, Lab 7 Preparation of Alkyl Halides by Substitution Reactions, Lab 8 Preparation of Alkenes by E1 and E2 Substitution Reactions, Baeyer and Bromine Test Used for Saturation, Lab 4 Steam Distillation of (S)-(+)-Carvone from Caraway Seeds and (R)-(–)-Carvone from Spearmint Leaves, Lab 10 Williamson Ether Synthesis Preparation of Phenacetin from Acetaminophen. the other solution was place inside. For benzoic acid the range is from 121-123°C while our experimental melting point was 99.9°C. According to the equation, several small extractions are more effective than one large. Lab 5: Base Extraction of Benzoic Acid from Acetanilide Recrystallization of Products Meaning, if K>1, then the sample is mainly in the. For this experiment we used a liquid-liquid base extraction (NaOH)aq. The differences in polarity, allows us to use, partition coefficient, to determine the amount of sample in each phase at a given, temperature. The straight line behavior of such plots is characteristic of the solubility of water in halogenated hydrocarbons, as discussed in the Preface.
4 and 5) are several per cent higher than the smoothed solubility values and are also rejected. The solubility measurements cover the 253 to 313 K temperature sample that has been separated is used to identify their respective percent yields.
6) between 293.15 and 303.15 K show a temperature dependence of solubility much too large and are therefore rejected. containing benzoic acid and acetanilide. 25), Hutchinson et al. temperature it is then placed into an ice bath.
(ref. had remained in the funnel was poured into a 50 mL beaker. The curve obtained from the smoothing equation shows a distinct minimum range. There percent yields were 44% and 30% in there respective order. Lastly, the sample was taken to IR and NMR machine to Base Extraction of Benzoic Acid from Acetanilide. (ref.
10), van Arkel and Vles (ref. The solubility data of Booth and Everson (ref.
HCl and placed into an ice bath. For 26), Leighton and Calo (ref. Percent yield =0.50 0.22 gg x 100 = 44% (ref. Percent error =|theoreticaltheoretical−actual| x 100, Calculations The remaining data of 11 laboratories by Staverman (Ref. Benzoic Acid The solubility measurements cover the 253 to 313 K temperature range as represented in Figure 2. It should be notable that you should see crystals forming at this, Chemical Mass of crystals (g) Temperature of Melting graduated cylinders, a 3 mL sample of NaOH was collected and a 10 mL sample of methylene release the gas pressure that was forming. temperature. 11), Bakowski and Treszczanovicz (ref. melting point was 117.9°C. After this was completed there should be two layers organic layer. 20), Archer and Stevens (ref. in the substance and to ensure separation of each.
The precipitation ability of the solid is dependent upon the Experimental Procedure (ref. trend of temperature dependence of solubility and are rejected; however, the The recommended mass percent solubility values at 5 K intervals for dichloromethane (1) in water (2) are presented in the Table 1.