Percent yield is calculated using the formula:Percent yield = Actual yield / Theoretical yield 100In this case, the actual yield of product B is 22 grams, and the theoretical yield assuming complete reaction is 28 grams.Percent yield = 22 grams / 28 grams 100Percent yield = 0.7857 100Percent yield 78.57%The percent yield of product B for this chemical reaction is approximately 78.57%.