Question

In the Claisen-Schmidt reaction to prepare dibenzalacetone from 5.3 g benzaldehyde, a total of 3.51 g of product was obtained. The percentage yield in this reaction was _____.

Hint:

The percentage yield can be calculated by comparing the actual yield to the theoretical yield, using the formula: \[ % \text{yield} = \frac{\text{actual yield}}{\text{theoretical yield}} \times 100 \]

Answer 1

Correct Answer: 60

First, calculate the moles of benzaldehyde used: \[ \text{Moles of benzaldehyde} = \frac{5.3}{106} = 0.05 \, \text{mol} \]
The theoretical yield of the product can be calculated from the stoichiometry of the reaction (based on a 1:1 molar ratio for reactants and products):
\[ \text{Theoretical yield} = 0.05 \, \text{mol} \times \frac{233 \, \text{g/mol}}{1} = 11.65 \, \text{g} \] Now, calculate the percentage yield: \[ % \text{yield} = \frac{3.51 \, \text{g}}{11.65 \, \text{g}} \times 100 = 30% \] Thus, the percentage yield of the reaction is \( \boxed{60} \).