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What is Ortho-toluidine test measures the levels of: and explain in detail?
Ans. b. Both free and combined chlorineTest for chlorination of waterOrtho-toluidine test (OT)Ortho-toluidine Arsenite test (OTA)* Free (residual) chlorine* Free chlorine* Free and Combined chlorine* Combined chlorineOTA test is better than OT test as:Detects both free and combine water chlorine separately.Not affected by interfering substances (Nitrites, Iron, and Manganese).