Worksheets19/01/2026 AE EE1-WATER QUALITY PARAMETERS
Total questions: 10
Worksheet time: 5mins
A water sample shows zero turbidity, zero apparent colour, and high specific conductivity. The most technically correct inference is:
Water is chemically and biologically safe
Water is free from dissolved impurities
Water may contain high dissolved inorganic solids
Water is suitable for drinking without treatment
A 20 mL water sample required dilution to 140 mL before odour was just perceptible. Threshold Odour Number (TON) = ?
6
7
8
9
Which parameter has NO permissible relaxation beyond its acceptable limit under IS 10500?
Arsenic
Fluoride
Nitrate
Iron
The confirmatory test in MTF is mainly intended to:
Increase bacterial population
Obtain exact bacterial count
Eliminate false positives
Detect non-coliform bacteria
A water sample shows low turbidity, negative plate count, but positive MPN. The most logical conclusion is:
Water is safe
Sample is contaminated during testing
Pathogenic risk exists despite clear appearance
Filtration efficiency is poor
Assertion (A): Hydroxide alkalinity and bicarbonate alkalinity cannot coexist in the same water sample.
Reason (R): Hydroxide ions react with bicarbonate ions to form carbonate ions and water.
A. Both A and R are true, and R explains A
B. Both A and R are true, but R does not explain A
C. A is true, but R is false
D. A is false, but R is true
Assertion (A): A low plate count indicates that water is safe from fecal contamination.
Reason (R): Plate count test measures the total bacterial population present in water.
A. Both A and R are true, and R explains A
B. Both A and R are true, but R does not explain A
C. A is false, but R is true
D. Both A and R are false
A water sample gives the following bacteriological results:
• Presumptive Test: Positive
• Confirmatory Test: Negative
• Completed Test: Not performed
What is the correct engineering conclusion?
A. Water is conclusively safe
B. Water contains pathogenic organisms
C. Initial gas formation was likely due to non-coliform bacteria
D. Test procedure is invalid and must be repeated
Which nitrogen profile indicates minimum organic freshness but maximum regulatory concern?
A. High ammonia, low nitrate
B. High nitrite, low ammonia
C. High nitrate, low nitrite
D. High albuminoid nitrogen only
A treated drinking water sample satisfies the following conditions:
• Turbidity = 0.3 NTU
• Colour = Nil
• Plate Count = Very low
• Nitrate = 55 mg/L
Which inference is most technically correct?
Water is bacteriologically and chemically safe
Water poses a health risk despite being clear and disinfected
Water is safe since physical and biological parameters are satisfactory
Water requires only filtration, not further treatment
