Which statement is not true for physisorption?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Chemical bond is responsible.
Physisorption involves weak van der Waals forces. It does not involve formation of chemical bonds.
Option 1: It is not specific in nature -Physisorption depends mainly on surface area and intermolecular forces. Hence it is generally non-specific. This is true.
Option 2: It is reversible in nature - Due to weak forces, adsorption can be reversed easily by changing temperature or pressure. This is true.
Option 3: Enthalpy of adsorption is low - Physisorption involves weak forces. So heat of adsorption is low. This is true.
Option 4: Chemical bond is responsible -Physisorption occurs due to weak van der Waals forces, not chemical bonds. Chemical bonds are involved in chemisorption. Hence this statement is not true.