Activated carbon is particularly effective at removing which pollutants from water?

• A. Organic compounds and odors.
• B. Heavy metals as hydroxides.
• C. Inert gases like helium.
• D. Large particulate matter.

Answer: (A)

Activated carbon works mainly through adsorption, where molecules stick to a huge, highly porous surface. Its enormous surface area and pore structure trap many organic molecules and volatile compounds in water, which is why it’s especially good at removing organic contaminants and odors such as solvents, pesticides, and taste-altering compounds. This is less effective for removing dissolved metals like heavy metal ions, which are typically handled by precipitation as hydroxides or by ion-exchange resins, not by adsorption on carbon. Inert gases such as helium interact very weakly with carbon surfaces, so they aren’t efficiently captured by activated carbon. Large particulate matter is better removed by physical filtration media rather than adsorption. So, the pollutants that activated carbon is best at removing are organic compounds and odors.