Which of the following is NOT a characterstic of chemisorption?

Identify which option is not a characteristic of chemisorption:

Chemisorption involves the formation of chemical bonds between adsorbate and adsorbent, making it highly specific—option (A) is characteristic.

The heat released is typically in the range $40-200 \mathrm{~kJ} / \mathrm{mol}$, aligning with chemical bond energies—option (B) is characteristic.

Chemisorption is unimolecular; strong covalent bonds occupy surface sites, preventing multilayer formation, which is a trait of physisorption—option (C) is not characteristic.

The process is irreversible due to high activation energy for desorption—option (D) is characteristic.

The answer is $\boxed{C}$.