The main objective of extraction is to isolate and purify organic substances. A chemist is able to achieve this by using either macroscale or microscale extraction for separating a solute from a solvent. Macroscale extraction uses a separatory funnel, while microscale extraction involves a conical vial. However, these experiments for extracting caffeine and isolating a neutral compound uses the macroscale extraction technique. Data Table 1 shows the results gathered from the first extraction experiment, though there has been an error. Originally, 0.170 g of caffeine was the starting amount that was made into a solution. However, 0.196 g of caffeine was determined to be found in the methylene chloride layer. A possible error that had occurred
…show more content…
A different Erlenmeyer flask has been used for the mass. As a result, the mass of the isolated caffeine is inaccurate. Though the product of this experiment was not successful, the extraction technique was better understood to carry out a second experiment - isolating a neutral compound with a base an acid impurity.
There were two parts to the isolating a neutral compound experiment. First, an acid impurity have to be tested. After two extractions of the aqueous layer, using macroscale technique, 6M HCl were added to each layer - in separate flasks - until both mixtures are acidic. Based on Data Table 4, it took more drops of HCl to acidify the first flask than the second flask. There was much more precipitate in the first flask as well. This most likely indicated that the acid impurity had been removed from the ether layer that had contained the unknown neutral layer - the more …show more content…
In this experiment, it was to extract a solute, benzoic acid, from immiscible solids. However, there has been an error in the selection of solute - sodium benzoate was to be extracted instead. This extraction technique was much simpler to achieve the product, as the organic layer was extracted using a pipette and not a separatory funnel. After experimentation, the results were gathered in Data Table 2. This experiment was conducted successfully, as the mass of the solid solute found was 0.012 g - a very reasonable amount, considering the starting 0.100 g in the mixture. The distribution coefficient was also determined for the solid between the methylene chloride and water layers; it was found to be 0.13. A third of the class’ Kd values for sodium benzoate was gathered, and they were similar. Sodium benzoate has a distribution coefficient of
A different Erlenmeyer flask has been used for the mass. As a result, the mass of the isolated caffeine is inaccurate. Though the product of this experiment was not successful, the extraction technique was better understood to carry out a second experiment - isolating a neutral compound with a base an acid impurity.
There were two parts to the isolating a neutral compound experiment. First, an acid impurity have to be tested. After two extractions of the aqueous layer, using macroscale technique, 6M HCl were added to each layer - in separate flasks - until both mixtures are acidic. Based on Data Table 4, it took more drops of HCl to acidify the first flask than the second flask. There was much more precipitate in the first flask as well. This most likely indicated that the acid impurity had been removed from the ether layer that had contained the unknown neutral layer - the more …show more content…
In this experiment, it was to extract a solute, benzoic acid, from immiscible solids. However, there has been an error in the selection of solute - sodium benzoate was to be extracted instead. This extraction technique was much simpler to achieve the product, as the organic layer was extracted using a pipette and not a separatory funnel. After experimentation, the results were gathered in Data Table 2. This experiment was conducted successfully, as the mass of the solid solute found was 0.012 g - a very reasonable amount, considering the starting 0.100 g in the mixture. The distribution coefficient was also determined for the solid between the methylene chloride and water layers; it was found to be 0.13. A third of the class’ Kd values for sodium benzoate was gathered, and they were similar. Sodium benzoate has a distribution coefficient of