• Arizona State University

• CHM 234

Raghav Agarwal Partner: Rishika Virdee Lab TA: Christa Lab Day: Tuesday, 2:50-5:20 PM Abstract: This experiment was done over a two-week period. In the first week, benzoin was synthesized to benzil, and in the second week, benzil was synthesized to benzilic acid. The reaction was synthesized by performing a reflux, crystallization, and recrystallization once for each reaction. The product was then characterized by taking an IR spectra and the melting point. The melting point range of the benzil was found to be 89.6°C-92.4°C while the melting point range of the benzilic acid was found to be 148.7°C-149.3°C. The percent yield of benzil from benzoin was 53.28% while the percent yield of benzilic acid from benzil was 33.06%. Introduction: The goal of this experiment is to synthesize benzilic acid from benzoin. In general, synthesis is a laboratory technique in which through reactions, a new product can be created. This allows scientists to synthesize more complex chemicals. The synthesis done in this experiment includes the steps of the reaction being done, isolation, purification, and finally characterization. In this specific lab, nitric acid is used to deprotonate the benzoin in the first reaction. In the second reaction, acid, potassium hydroxide, and heat are used to reduce the benzil. The first technique for the reaction is reflux. In reflux, a condenser is used so the reaction solution (benzoin and nitric acid in this case) can be heated without losing any product from evaporation as condensation happens consistently. The reason that the reaction is heated in the first place is to increase the energy of the system. As the heat increases, the thermal energy of the particles increases, which increases the energy to the activation energy level At this point, the bonds are able to break and the collisions form the reactions. Once the reaction has taken place, the technique of filtration is used to isolate the product. After filtration, the moles of the final product will be used over the moles of the starting reactant to calculate the percent yield. Once this is calculated, the product is characterized using the lab technique of IR spectrum analysis and melting point analysis. These both may be compared to established samples to determine the accuracy of the product. In addition, the narrower the melting range is, the more pure the product is.