Water-soluble pesticides are more attracted to clay particles than oil-soluble pesticides.

• A. True
• B. Sometimes
• C. Not sure
• D. False

Answer: (A)

The main idea is how pesticide polarity affects where it sticks in soil. Clay minerals have surfaces with negative charges and lots of hydroxyl groups, which means polar or ionic pesticide molecules can interact there through electrostatic forces and hydrogen bonding. Water-soluble pesticides, being polar, are more attracted to these charged and hydrated clay surfaces than nonpolar ones. Oil-soluble pesticides, on the other hand, are hydrophobic and tend to partition into organic matter rather than cling to clay surfaces, so they’re less drawn to clay. Because of these interactions, water-soluble pesticides are typically sorbed more to clay particles than oil-soluble pesticides. This difference helps explain why soil texture and composition influence pesticide fate and mobility.