Question

Reaction Calculations (fill in the blanks) C_6 H_5 Br + Mg^0 rightarrow C_7 H_5 O_2 MgBr + CO_2 rightarrow C_7 H_6 O_2 Show calculations to determine the theoretical yield of benzoic acid that can form using the amounts of reagents above.

Answer 1

First, calculate amount of moles

mol of C6H5Br --> mass/MW = 0.70/157.01 = 0.0044583

mol of Mg--> mass/MW = 0.10/24.31 = 0.0041135

mol of CO2 --> 3/44 = 0.10/24.31 = 0.00411

clearly, Mg is limiting reaction so

0.0041135 mol of Mg will react with 0.0041135mol of C6H5Br to form 0.0041135mol of CO2

theoretical yield of benzoic acid ---> 0.0041135 mol of intermediate --> 0.0041135 mol of benzoic acid

mass = mol*MW 0.0041135 * 122.123 = 0.50235 g of Benzoic Acid

that is the maximum amount of B.Acid for a 100% conversion