Download Prelab for Experiment 2: Extraction - Organic Chemistry with Lab | CHEM 2050 and more Lab Reports Organic Chemistry in PDF only on Docsity! Prelab for Experiment #2: Extraction Your Name: Name of TA: Lab partner’s name: Lab Section: Title: Experiment #1: Extraction Purpose: In this lab, we will partition materials between various solvents, based upon their acid/base properties. Reagents Table: Name of Reagent M.W. (g/mol) M.P. (oC) B.P. (oC) Density (g/ml) Hazards Biphenyl 154 70 toxic Benzoic Acid 122 122 Contact hazard p-Nitroaniline 138 146 poison Methylene Chloride 85 39.8 1.32 Carcinogen, toxic 3M HCl Corrosive, Toxic 3M NaOH Corrosive, Toxic 6M NaOH Corrosive, Toxic 6M HCl Corrosive, Toxic Procedure: 1. Weigh out 3 grams of the chemical mixture. Dissolve the mixture in 40 ml of CH2Cl2 with gentle heating. After all solids have dissolved, pour the solution into a separatory funnel. 2. Rinse the initial flask (used to dissolve mixture) with 10 ml CH2Cl2 and pour this solution to the separatory funnel as well. 3. Add 15ml of 3M HCl and mix gently and vent. Allow the layers to separate and determine which one is the organic layer. Collect the top (aqueous layer) in a container labeled HCl extract. Place the lower organic layer into the separatory funnel and re-extract with another 15ml of 3M HCl. Collect the aqueous extraction from the second extraction in the same container that was labeled HCl extract. Keep this container (HCl extract) on ice. Once the HCl extract is cold, add 6M NaOH dropwise till a precipitate is formed and red litmus paper turns blue. Chill solid and vacuum filter solid followed by washing the crystals with chilled water. 4. Dry crystals and find the weight of p-nitroaniline. Do Not Recrystallize! 5. Place the lower organic layer once again in the separatory funnel. Add 15ml of 3M NaOH and mix gently and vent. Allow the layers to separate and collect the top (aqueous layer) in a container labeled NaOH extract. Place the lower organic layer back into the separatory funnel and re-extract with another 15ml of 3M NaOH. Collect the aqueous extraction from this extraction in the same container that was labeled NaOH extract. Keep this container (NaOH extract) on ice as well. Once the NaOH extract is cold, add 6M HCl dropwise till a precipitate is formed and blue litmus paper turns red. Chill solid and vacuum filter solid followed by washing the crystals with chilled water.
