Answer: Reversible with low enthalpy of adsorption.
- A Highly specific and irreversible
- B Reversible with low enthalpy of adsorption
- C Always increases with rising temperature
- D Requires very high activation energy
Correct answer: B. Reversible with low enthalpy of adsorption
Explanation: Physisorption is generally reversible and has a low enthalpy of adsorption, typically 20 to 40 kJ per mole.
A typical adsorption isotherm: x/m (mass adsorbed per gram of adsorbent) rises steeply at low pressure, then flattens into a saturation plateau as the adsorbent surface fills up.
Concept context
Explore the chemistry that happens at interfaces, from catalysts that speed up industrial reactions to colloids like milk, smoke, and gels that surround us every day.