Chlorine effectiveness is influenced by what factor?

Chlorine effectiveness in water treatment is significantly influenced by the pH of the water. The pH level affects the form in which chlorine exists in the water. At lower pH levels (more acidic conditions), chlorine is primarily present as hypochlorous acid, which is much more effective at killing microorganisms than its ionized form, hypochlorite ion, which predominates at higher pH levels. This means that maintaining an appropriate pH level is crucial for maximizing the disinfecting power of chlorine in water.

While temperature can also impact the reaction rates of chlorine and the microorganisms, the direct influence of pH on the chemical forms of chlorine makes it a more critical factor in assessing chlorine effectiveness. Water pressure and turbidity are also important in other contexts but do not have the same direct impact on chlorine's disinfecting properties as pH does.