What is the theoretical yield of (CH_3)_3, CO^- K^+ from 12 mL (CH_3) _3 COH and 3 g potassium metal? 2 (CH_3)_3COH + 2K rightarrow 2 (CH_3)_3CO^-K^+ H_2 As mentioned above, organic reactions rarely produce the theoretical quantity of product. Thus, we divide the actual, observed yield by the theoretical yield to give a percent yield - for example, a reaction might produce 60% of the theoretical yield. % yield = observed yield/theoretical yield times 100 %. A student expecting 2.5 grams from a synthesis of aspirin obtained 1.7 g. What was the percent yield for this reaction?