Preview Questions Water Treatment Operator | Role Specific Skill

Question 1: How does the addition of sodium hypochlorite differ from other forms of chlorine in water disinfection?

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It is less corrosive and can be used safely in a wider pH range

It produces fewer disinfection by-products

It is more effective than other chlorine forms at high temperatures

It requires longer contact times to be effective

Question 2: How do you evaluate the effectiveness of a granular activated carbon (GAC) system in removing trace organic contaminants from water?

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By assuming that all contaminants are equally removed

By focusing only on flow rate without considering GAC adsorption efficiency

By ignoring the frequency of carbon regeneration and its impact on system performance

By measuring adsorption capacity, breakthrough curves, and monitoring effluent quality

Question 3: In water quality testing, which of the following is used to measure the chemical oxygen demand (COD) of a water sample?

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Phosphoric acid in a colorimetric test

Sodium hypochlorite

Sodium bicarbonate in a buffered solution

Potassium dichromate in acidic solution

Question 4: In the context of water quality testing, what does the term "volatile suspended solids" (VSS) refer to?

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The inorganic fraction of suspended solids that do not decompose

The solids that remain in the water after disinfection

The organic fraction of suspended solids that can decompose biologically

The solids that are filtered from the water after coagulation

Question 5: When using sulfur dioxide for dechlorination, what must be carefully monitored to avoid under or over-chlorination?

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The turbidity of the water before dechlorination

The flow rate of the sulfur dioxide

The amount of chlorine present in the water

The pH level of the treated water

Question 6: Which testing method is most commonly used to detect heavy metals in water?

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High-performance liquid chromatography (HPLC)

Atomic absorption spectroscopy (AAS)

Fluorescence microscopy

Gas chromatography (GC)