The DPD method is used to measure which parameter?

The DPD method is used to measure which parameter?

• A. Amperometric titration
• B. pH indicator method
• C. Turbidity measurement
• D. DPD method (colorimetric)

Answer: (D)

DPD method is a colorimetric test used to measure chlorine residuals in water. DPD stands for N,N-diethyl-p-phenylenediamine. When chlorine is present, the DPD reagent is oxidized and turns a pink to reddish color, with the color intensity proportional to the chlorine concentration. You read the result by comparing to a color chart or using a photometer. This approach is specifically about detecting chlorine through a color change, not about electrical titration, pH, or turbidity measurements.

DPD method is a colorimetric test used to measure chlorine residuals in water. DPD stands for N,N-diethyl-p-phenylenediamine. When chlorine is present, the DPD reagent is oxidized and turns a pink to reddish color, with the color intensity proportional to the chlorine concentration. You read the result by comparing to a color chart or using a photometer. This approach is specifically about detecting chlorine through a color change, not about electrical titration, pH, or turbidity measurements.