Which of the following factors would reduce the percent yield of a chemical reaction?

• A. Using pure reactants with no impurities
• B. Efficient separation and recovery of product
• C. Optimal reaction temperature and pressure
• D. Incomplete reaction due to insufficient reactant mixing

Answer: (D)

Verified step by step guidance

1. Understand that percent yield is calculated by comparing the actual amount of product obtained to the theoretical maximum amount possible, using the formula: \(\text{Percent Yield} = \left( \frac{\text{Actual Yield}}{\text{Theoretical Yield}} \right) \times 100\%\).
2. Recognize that factors improving reaction conditions, such as using pure reactants, efficient separation, and optimal temperature and pressure, generally increase the percent yield by maximizing product formation and recovery.
3. Identify that incomplete reactions, such as those caused by insufficient mixing of reactants, prevent the reaction from proceeding fully, thus lowering the actual yield.
4. Conclude that incomplete reaction due to poor mixing reduces the amount of product formed, directly decreasing the percent yield.
5. Therefore, among the options, incomplete reaction caused by insufficient reactant mixing is the factor that would reduce the percent yield.