AP EAMCET201920 Apr 2019Evening ShiftChemistrySurface ChemistryActual
Which of the following statements is not correct?
Options
- ABoth physical and chemical adsorptions are exothermic
- BPhysical adsorption takes place with decrease of free energy whereas chemical adsorption occurs with increase
- CPhysical adsorption requires low activation energy but chemical adsorption requires high activation energy
- DThe magnitude of chemical adsorption increases and that of physical adsorption decreases with rise in temperat
Correct answer
B. Physical adsorption takes place with decrease of free energy whereas chemical adsorption occurs with increase
Step-by-step solution
Both physical and chemical adsorption are exothermic in nature. But, chemical absorption requires high heat of adsorption due to formation of chemical bond. Moreover, magnitude of chemical adsorption increases and that of physical adsorption decreases with the rise in temperature due to requirement of activation energy in case of chemical adsorption. Thus, option (b) is incorrect.