Theoretical Yield

Question

The theoretical yield of a reaction is the amount of product obtained if the limiting reactant is completely converted to product.

Consider the reaction:

C(s) + O₂(g) → CO₂(g)

If 15.51 g C is mixed with 15.18 g O₂, calculate the theoretical yield (g) of CO₂ produced by the reaction.

Answer 1

To determine the limiting reagent, convert grams of each reactant to moles of CO₂. The reactant that produces less CO₂ is the limiting reagent.

15.51 g C x (1 mol C / 12.01 g C) x (1 mol CO₂ / 1 mol C) = 1.291 mol CO₂

15.18 g O₂ x (1 mol O₂ / 32.00 g O₂) x (1 mol CO₂ / 1 mol O₂) = 0.4744 mol CO₂

From above, you can see that O₂ produces less CO₂, therefore, it is the limiting reagent. Theoretical yield of CO₂ is

0.4744 mol CO₂ x (44.01 g CO₂ / 1 mol CO₂) = 20.88 g CO₂