Which statement correctly describes adsorption in soil?

Which statement correctly describes adsorption in soil?

• A. A pesticide held strongly to soil particles that is less likely to leach
• B. A pesticide that evaporates quickly
• C. A pesticide that moves with water
• D. A pesticide that is broken down by sunlight

Answer: (A)

Adsorption in soil is the attachment of a pesticide to soil solids, such as clay and organic matter. When a pesticide adsorbs strongly to these particles, it stays with the solid phase and is less available to move with soil water, making it less likely to leach toward groundwater. That’s why describing a pesticide as held tightly to soil particles and less likely to leach best captures adsorption. If a pesticide evaporates quickly, that’s volatilization, not adsorption. A pesticide that moves with water is being transported with the soil solution, indicating low adsorption and higher mobility. A pesticide broken down by sunlight is undergoing photodegradation, a degradation process rather than a transport or binding process.

Adsorption in soil is the attachment of a pesticide to soil solids, such as clay and organic matter. When a pesticide adsorbs strongly to these particles, it stays with the solid phase and is less available to move with soil water, making it less likely to leach toward groundwater. That’s why describing a pesticide as held tightly to soil particles and less likely to leach best captures adsorption.

If a pesticide evaporates quickly, that’s volatilization, not adsorption. A pesticide that moves with water is being transported with the soil solution, indicating low adsorption and higher mobility. A pesticide broken down by sunlight is undergoing photodegradation, a degradation process rather than a transport or binding process.