Water Nuggets Practice Exam

Which factor would have the least impact on the efficiency of copper sulfate?

1. pH

2. Alkalinity

3. Water Hardness and Langlier Index

4. Water Temperature

The correct answer is: pH

The least impact on the efficiency of copper sulfate would indeed be pH. Copper sulfate's effectiveness as an algaecide or fungicide is influenced primarily by various water chemistry factors, particularly those that affect the solubility and bioavailability of the copper ions. While pH can certainly play a role in the overall chemistry of water and can influence the speciation of copper ions, it generally does not have as pronounced an effect on the efficiency of copper sulfate compared to other factors. For instance, water temperature significantly affects the reaction rates and solubility of compounds, while water hardness and the Langlier Index provide insights into scaling potential and nutrient bioavailability, which can directly affect copper sulfate's action. Alkalinity also impacts the overall buffering capacity of water which can influence how the chemical behaves. In this context, although pH is a crucial parameter in aquatic chemistry, it has relatively less direct influence on the specific effectiveness of copper sulfate compared to the other factors mentioned.