preview

Multistep Synthesis Essay

Satisfactory Essays

Results:

Limiting Reactant: Eq 1 Limiting reactant = Benzoin

Theoretical yield of Benzil:

Eq 2

Theoretical Yield Benzil | 0.296 g | Mass of Crude Benzil | 0.188 g | Mass of Final Benzil | 0.127 g | % Yield | 43% | % Recovery | 66% |
Table 1: Mass of crude/final Benzil, % yield, and % recovery

Percent Yield: % Yield = (Final product/Theoretical product) x 100 Eq 3 = (0.127 g/0.296 g) x 100 = 43% yield

Percent Recovery % Recovery = (Final product/Crude product) x 100 Eq 4 = (0.127 g/0.188 g) x 100 = 66% recovery

Theoretical Yield Benzilic Acid:

Eq 5

Theoretical Yield Benzilic Acid | 0.109 g | Final Benzilic Acid | 0.060g | …show more content…

The percent yield, calculated using the theoretical and final amount of benzil, was 43% (see Eq 3). The percent recovery, calculated using the crude and final amount of benzil, was 66% (Eq 4). The melting points of crude and final benzil were 82.5 – 85.6C and 94.2C respectively (Table 3). The literature value for pure benzil is 95C and the final crystallized benzil temperature value is very close to the literature value. This testifies the purity of the experimental benzil. The melting point value of the crude was much lower and the range was much wider due to the impurities. For further conformation of the purity of experimental benzil, the infrared spectroscopy was observed. . The following functional groups were determined on the infrared spectroscopy according to their corresponding wavenumbers: aromatic, sp2 C-H bonds, and C=O/carbonyl group (Table 4). Benzil incorporates all of the above functional groups. The melting and infrared spectroscopy confirmed that the final product created was Benzil.
In the following reaction, benzil was rearranged to from benzilic acid by reacting it with potassium hydroxide in ethanol. 0.100 benzil was utilized and the theoretical yield of benzilic acid was 0.109 grams (see Eq 5). The final yield and weight of benzilic acid was 0.60 grams. The final yield and theoretical yield were used to calculate the percent yield, 55% (similar to Eq 3). The melting point of benzilic acid was 148.3C and the literature value for

Get Access