Water Nuggets Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

The effectiveness of chlorination in water treatment largely depends on the pH of the water. Chlorine's disinfection capabilities vary significantly with changes in pH; at a lower pH, chlorine exists primarily as hypochlorous acid (HOCl), which is much more effective at killing bacteria and pathogens compared to other forms of chlorine that become prevalent at higher pH levels.

Optimal chlorination occurs within a pH range of 6.5 to 7.5, allowing for the best balance of hypochlorous acid formation. As pH levels rise above this optimal range, the proportion of less effective hypochlorite ion (OCl-) increases, diminishing chlorine's effectiveness. Thus, monitoring and controlling pH is essential for ensuring that chlorination achieves its intended purpose of maintaining safe water quality.

While other parameters like TDS, hardness, and alkalinity can influence water quality and treatment processes, they do not have nearly the same direct impact on chlorination efficiency as pH does. For instance, TDS can affect the conductivity and overall chemical balance of water, hardness relates to calcium and magnesium concentrations, and alkalinity measures the water's capacity to resist pH changes; none of these factors are as critical to