Question

After breakpoint chlorination chlorine remains as

Answer 1

Only after the oxidant demand has been addressed can disinfection occur. Therefore, only after breakpoint chlorination has been exceeded can a residual of free chlorine build. Up until that point, chlorine has its hands full trying to oxidize its way to breakpoint.

Answer 2

Answer:

Breakpoint chlorination is the point where the demand for chlorine has been fully satisfied in terms of chlorine addition to the water. In other words, the chlorine has completely reacted with the bather pollutants leaving a zero chlorine residual.