Question

A reaction between 1.7 moles of zinc iodide and excess sodium carbonate yields 12.6 grams of zinc carbonate. This is the equation for the reaction: Na2CO3 + ZnI2 → 2NaI + ZnCO3. What is the percent yield of zinc carbonate?

Answer 1

A reaction between 1.7 moles of zinc iodide and excess sodium carbonate yields 12.6 grams of zinc carbonate. The equation for the reaction is given as follows: Na₂CO₃ + ZnI₂ → 2NaI + ZnCO₃. Then the percent yield of zinc carbonate can be calculated as follows;

First the mole ratio of zinc iodide to zinc carbonate is 1:1 therefore 1.7 moles of zinc carbonate is theoretically produced.

So theoretical yield of zinc carbonate is= Moles x relative formula mass of zinc carbonate

    1.7 x 124= 210.8 grams

Hence percentage yield= actual yield/theoretical yield x 100

                                       = 12.6/210.8 x 100

                                       = 6%.