How do impurities impact percentage yield?

Impurities can decrease the percentage yield by interfering with the reaction process or by contaminating the final product.

Impurities in a chemical reaction can have a significant impact on the percentage yield. This is because they can interfere with the reaction process, leading to a lower yield than expected. For instance, if an impurity reacts with one of the reactants, it can reduce the amount of that reactant available for the intended reaction. This would result in a lower yield of the desired product.

Moreover, impurities can also contaminate the final product, making it difficult to separate the desired product from the impurities. This can lead to a lower measured yield, as some of the product may be lost during the purification process. For example, if an impurity is soluble in the solvent used to purify the product, it may be washed away with the impurity during the purification process, reducing the amount of product that can be collected.

In addition, impurities can also affect the rate of reaction. If an impurity acts as a catalyst, it can speed up the reaction, potentially leading to a higher yield. However, if an impurity acts as an inhibitor, it can slow down the reaction, potentially leading to a lower yield.

Therefore, it is crucial to use pure reactants in a chemical reaction to achieve the highest possible yield. This is why in a laboratory or industrial setting, chemists often go to great lengths to purify their reactants before starting a reaction. It's also important to consider the potential impact of impurities when calculating theoretical yields and planning chemical reactions.