Benzoic acid (molar mass $122 g mo l^{- 1}$ ) is converted by Birch reduction into cyclohexa-2,5-diene-1-carboxylic acid (molar mass $124 g mo l^{- 1}$ ). Starting from $12.2 g$ of benzoic acid and obtaining an isolated yield of $80%$ , what mass of the diene acid is obtained? Give the answer in grams to two decimal places.

Numerical answer type, answer in g, tolerance 0.05.

Answer: 9.92 g

Moles of benzoic acid are

12.2/122 = 0.100

. The reaction is one-to-one, so the theoretical yield is

0.100 \times 124 = 12.4 g

. At

80%

yield the mass is

12.4 \times 0.80 = 9.92 g