Question

Which characteristic is not correct for physical adsorption?

• A. Adsorption is spontaneous.
• B. Both enthalpy and entropy change of adsorption are negative.
• C. Adsorption on solid is reversible.
• D. Adsorption increases with increase in temperature.

Answer 1

The correct option is D Adsorption increases with increase in temperature.

Physical adsorption decreases with increase in temperature.
Physical adsorption is non-directional, reversible, multilayers exothermic process where adsorbate molecules are held on surface of adsorbent by physical forces such as van der Waals forces.

Van der Waals interactions cause these surface atoms to be reactive, causing them to attract liquids, vapors and gases in order to satisfy their atomic force imbalance. The attracted molecules fill in the pores on the surface of the solid when adsorption occurs.