In the following reaction sequence, the amount of D (in g) formed from 10 moles of acetophenone is ____.
(Atomic weights in gmol−1: H=1, C=12, N=14, O=16, Br=80. The yield (%) corresponding to the product in each step is given in the parenthesis)
Answer: 495
Solution
Starting with 10 moles of acetophenone (MW = 120), the reaction sequence with given yields produces compound D. Following the transformations and multiplying by the yields at each step: 10 moles × 0.8 × 0.5 × 0.75 × 0.5 = 1.5 moles of D. The molecular weight of D (tribromoacetophenone derivative) is 330 g/mol. Amount of D = 1.5 × 330 = 495 g.
JEE Advanced · 2018 · 20 May 2018 · Paper 2 · Numerical answer