In a chemical reaction, benzene is nitrated to produce nitrobenzene with a 60 % yield. The mass of benzene required to produce 12.3 g of nitrobenzene is ________ g . (Given atomic masses in g mol ⁻¹ : C =12 , H =1 , N =14 , O =16 )

Step-by-step solution

Molar mass of nitrobenzene ( C ₆ H ₅ NO ₂ ) = (6 12) + (5 1) + 14 + (2 16) = 123 g mol ⁻¹ Moles of nitrobenzene produced = 12.3 123 = 0.1 mol Since the percentage yield is 60 % , the theoretical moles of nitrobenzene required = 0.1 0.6 = 1 6 mol The nitration of benzene ( C ₆ H ₆ C ₆ H ₅ NO ₂ ) has a 1:1 stoichiometry, so the moles of benzene required = 1 6 mol Molar mass of benzene ( C ₆ H ₆ ) = 78 g mol ⁻¹ Mass of benzene required = 1 6 78 = 13 g Answer: 13