Water Treatment Leaves Dissolved Minerals Intact

Steps:

• Standard water treatment includes screening, coagulation, flocculation, sedimentation, filtration, and disinfection.
• These processes remove suspended solids like sand and organic matter through settling and filtering.
• Disinfection eliminates harmful microbes via chemicals like chlorine.
• Dissolved substances, such as mineral salts, pass through unchanged as they are not particulate.

Why C is correct:

• Mineral salts are dissolved ions (e.g., Na+, Ca2+) that filtration and disinfection cannot remove, per basic solubility principles in water chemistry.

Why the others are wrong:

• A: Fine sand is a suspended solid captured by filtration beds.
• B: Harmful microbes are neutralized by disinfection agents like chlorine.
• D: Solid organic matter settles out during sedimentation or is filtered.

Final answer: C