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Essay about Synthesis of Benzilic Acid

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Synthesis of benzilic acid from benzoin utilizing a multi-step reaction. Names: Arian Karim TA Name: Sayantan Das Lab Day & Time: Thursday 7:30-11:40 Lab Section #: Abstract The main purpose of this experiment was to synthesize benzilic acid from benzoin. This requires a multistep synthesis with benzyl as an intermediate product. The first step required HNO3 as an oxidizing agent and the second step required KOH and HCl. The percentage yields of benzil and benzilic acid were 59.5% and 21.9% respectively. The calculated melting point of benzil was 90.1-91.6 which suggested some impurities, but the MP of benzilic acid was 149.3-151.5 which suggested a pure yield. The IR further confirmed the identity of benzylic acid with two …show more content…

The solution was then allowed to crystallize and the solid benzilic acid was dried, weighed, and used to obtain melting point and IR spectra. Results and Calculations: Figure 3: Part A Results | Mass of Reactant (g) | Theoretical Yield (g) | Mass of Crude Product (g) | Mass of Final Product (g) | % Yield | Theoretical Boiling Point (C) | Experimental Boiling Point (C) | 0.30 | 0.294 | 0.318 | 0.175 | 59.9 | 95 | 90.1-91.6 | Figure 4: Part B Results | Mass of Reactant (g) | Theoretical Yield (g) | Mass of Product (g) | % Yield | Theoretical Boiling Point (C) | Experimental Boiling Point (C) | 0.100 | 0.114 | 0.025 | 21.9 | 150 | 149.3-151.5 | Figure 5: Calculations | Part A: Benzoin to Benzil | | | | initial mass of benzoin | 0.30 g | | | MW of benzoin | 212.24 g/mol | | | | | | mol benzoin | = | mass / MW | | | = | .30 / 212.24 | | | = | 0.0014 | mol | | | | | MW benzil | = | 210.23 g/mol | | mass benzil | = | mol benzoin x MW benzil | | = | .0014 x 210.23 | | theoretical yield | = | 0.294 | g | | | | | actual yield benzil | = | 0.175 | g | % yield | = | actual/thr x 100% | | | = | .175 / .294 x 100% | | | = | 59.5 | % | | | | | Part B: Benzil to Bezilic Acid | | | initial mass of benzil | 0.10 g | | | MW of benzil | 210.23 g/mol | | | | | | mol benzil | = | mass / MW |

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