Answer:
Swimmers health.
Explanation:
The pH is the measure of the concentration of the ions H⁺ (pH = -log[H⁺]), and it determines if the substance is acidic, basic or neutral. If pH = 7, it's neutral, if it's below 7 it's acidic, and if it's above 7, it's basic.
In pool water, chlorine is added to disinfect it, by killing microorganisms. The pH of the water affects the action of the chlorine, and for a better result in disinfection, it must be between 7.0 and 7.6, so the disinfection will happen and the swimmers' health will be protected.
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