Engineering Board Exam Reviewer · Environmental Engineering · medium

Breakpoint chlorination is the point at which:

  1. All bacteria are killed instantly
  2. Chlorine reacts with hardness
  3. Chloramines are destroyed and free chlorine residual begins to rise
  4. No more chlorine can dissolve

Answer

C. Chloramines are destroyed and free chlorine residual begins to rise

Solution

Adding chlorine beyond the breakpoint gives a free available chlorine residual.

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