Which substance is an example of a chemical filter?

Which substance is an example of a chemical filter?

• A. Gravel
• B. Glass
• C. Activated carbon
• D. Plastic

Answer: (C)

A chemical filter removes dissolved contaminants by chemical interaction with the filter material, not just by trapping particles by size. Activated carbon has an extremely large surface area with many tiny pores, so dissolved chemicals, chlorine, odors, and various organic compounds can adsorb onto its surfaces as fluid passes through. That adsorption process is what makes activated carbon a chemical filter and why it’s used in water and air purification. Gravel filters mainly trap larger particles by size, providing a mechanical barrier rather than adsorbing dissolved substances. Glass can act as a barrier or support but doesn’t chemically bind contaminants in the way activated carbon does. Plastic alone doesn’t remove dissolved chemicals through adsorption. So activated carbon best fits the concept of a chemical filter.

A chemical filter removes dissolved contaminants by chemical interaction with the filter material, not just by trapping particles by size. Activated carbon has an extremely large surface area with many tiny pores, so dissolved chemicals, chlorine, odors, and various organic compounds can adsorb onto its surfaces as fluid passes through. That adsorption process is what makes activated carbon a chemical filter and why it’s used in water and air purification.

Gravel filters mainly trap larger particles by size, providing a mechanical barrier rather than adsorbing dissolved substances. Glass can act as a barrier or support but doesn’t chemically bind contaminants in the way activated carbon does. Plastic alone doesn’t remove dissolved chemicals through adsorption. So activated carbon best fits the concept of a chemical filter.