Consider the chemical equation. CuCl2 2NaNO3 Right arrow. Cu(NO3)2 2NaCl What is the percent yield of NaCl if 31. 0 g of CuCl2 reacts with excess NaNO3 to produce 21. 2 g of NaCl? Use Percent yield equals StartFraction actual yield over theoretical yield EndFraction times 100. 49. 7% 58. 4% 63. 6% 78. 7%.