Water Treatment and Effluent Management MCQs 2026

Ion exchange softener replaces Ca²⁺ with

1. A Cl₂ gas in water always ✓
2. B only oxygen molecules ✓
3. C Na⁺ on resin ✓
4. D only silica sand ✓

Breakpoint chlorination aims to

1. A increase BOD ✓
2. B add hardness ✓
3. C precipitate calcium only without disinfection ✓
4. D oxidize ammonia and organic chloramines ✓

Reverse osmosis removes ions by

1. A pressure-driven membrane rejection ✓
2. B only gravity sand filter alone for ions ✓
3. C only aeration alone for TDS ✓
4. D only UV alone for salinity ✓

Flocculation promotes

1. A dissolving all salts instantly ✓
2. B particle aggregation into settleable flocs ✓
3. C boiling river entirely ✓
4. D only RO membrane synthesis ✓

Coagulation in water treatment uses

1. A only reverse osmosis membrane only step ✓
2. B chemical to destabilize colloidal particles ✓
3. C only chlorination only without solids removal ✓
4. D only activated carbon only for dissolved organics without coag ✓