If 2.43 grams of aluminum react with excess CuSO4, What is the theoretic yeild of Cu? And then Use the Actucal amount of Cu formed to find percent yield.You have 0.92 mass of copper metal product.
2Al + 3CuSO4 ---> Al2(SO4)3 + 3Cu
2.43 / 27 = 0.09 moles of al
0.09 x 3 / 2 x 63.5 = 8.5725 is theretical yeild
0.92/ 8.5725 x 100 = 10.73 percent