Which statement best describes the effect of high pH on copper sulfate?

Which statement best describes the effect of high pH on copper sulfate?

• A. Higher pH causes copper to precipitate and become unavailable
• B. Lower pH causes copper to precipitate
• C. pH does not affect copper sulfate
• D. Copper sulfate becomes more effective at high pH

Answer: (C)

Copper sulfate in water behaves as a salt that dissociates into copper ions and sulfate ions. The amount of copper sulfate present as the dissolved salt is not directly determined by the solution’s pH under typical treatment conditions. In other words, simply changing pH does not alter how much copper sulfate is in the solution as CuSO4. Only at very high pH levels would copper ions start to form solid copper hydroxide, removing copper from solution, but that’s a precipitation of a different compound rather than a change to the copper sulfate itself. So, in this context, pH does not affect the copper sulfate molecule, which is why that statement is considered the best description.

Copper sulfate in water behaves as a salt that dissociates into copper ions and sulfate ions. The amount of copper sulfate present as the dissolved salt is not directly determined by the solution’s pH under typical treatment conditions. In other words, simply changing pH does not alter how much copper sulfate is in the solution as CuSO4. Only at very high pH levels would copper ions start to form solid copper hydroxide, removing copper from solution, but that’s a precipitation of a different compound rather than a change to the copper sulfate itself. So, in this context, pH does not affect the copper sulfate molecule, which is why that statement is considered the best description.