% yield = actual yield x100
Therefore, theoretical yield = actual
yield x100 =
90.0 x 100 = 94.7 g
theoretical
yield % yield 95
94.7g = 0.526 mol of aspirin
180g/mol
The molar
ratio of Salicylic acid to aspirin is 1:1.
Therefore the amount of Salicylic acid need is 0.526 mol which is
0.526 mol x
138 g/mol = 72.6g.