What is the percent yield for the reaction pcl3 (g) + cl2 (g) ? pcl5 (g) if 119.3 g of pcl5 (? = 208.2 g/mol) are formed when 61.3 g of cl2 (? = 70.91 g/mol) react with excess pcl3? a 66.3%?

The balanced chemical reaction would be

pcl3 (g) + cl2 (g) = pcl5 (g)

First, we need to determine the theoretical yield of the reaction assuming that all of the limiting reactant is used up. Then, we divide the actual yield to the theoretical yield to determine the percent yield.

Theoretical yield = 61.3 g Cl2 (1 mol / 70.9 g) (1 mol PCl5 / 1 mol Cl2) (208.2 g / 1 mol) = 180.01 g PCl5

Percent yield = 119.3 g / 180.01 g x100 = 66.3%