Activated Carbon Adsorbs Impurities

Steps:

• Recall that carbon in water purification refers to activated carbon, a porous material.
• Understand activated carbon's primary function: adsorption of dissolved organic compounds.
• Evaluate choices against this function to identify the best match.
• Confirm D aligns with removing taste- and odor-causing substances via adsorption.

Why D is correct:

• Activated carbon removes tastes and odours by adsorbing organic molecules onto its surface, as defined by the adsorption process where solutes bind to a solid.

Why the others are wrong:

• A: Filtration for solids uses media like sand or cloth, not carbon's adsorption.
• B: Carbon does not add oxygen; aeration or chemicals handle oxygenation.
• C: Disinfection uses chlorine or UV light, not carbon.

Final answer: D