Question

The given graphs I, II, III and IV represent the general trends observed for different physisorption and chemisorption processes under mild conditions of temperature and pressure. Which of the following choice(s) about I, II, III and IV is/are correct?

• A. I is physisorption and III is chemisorption.
• B. I is physisorption and II is chemisorption.
• C. IV is chemisorption and III is physisorption.
• D. IV is chemisorption and III is chemisorption.

Answer 1

Answer: (B), (C)

The correct options are
B I is physisorption and II is chemisorption.
C IV is chemisorption and III is physisorption.

Graph I represents physisorption beacuse the amount of adsorption decreases with increase in temperature.

Graph II represents chemisorption because the amount of adsorption increases with increase in temperature.

Graph III represents physisorption because the amount of adsorption increases with increase in pressure

Graph IV represents chemisorption as it represents the formation of a chemical bond.

From these observations we can conclude that options $\left(b\right)$ and $\left(c\right)$ are correct.