JEE Advanced
- Exam
- JEE Advanced
- Subject
- Chemistry
- Chapter
- Surface Chemistry
JEE Advanced · Chemistry · Surface Chemistry
How many of the following statements is/are true? (1) Silica gel...
How many of the following statements is/are true?
(1) Silica gel absorbs water molecule from moist air.
(2) The entropy of gas decreases when it gets adsorbed on charcoal.
(3) Heterogeneous catalysts like in the hydrogenation of vegetable oil function by chemisorption.
(4) The enthalpy of physisorption is smaller in magnitude than enthalpy of chemisorption.
(5) As temperature increase, the extent of physisorption decrease but it can get converted to chemisorption at higher temperature.
Graph A represent chemisorption and graph B represent physisorption.
Graph A represent chemisorption and graph B represent physisorption.
Correct answer
5
Step-by-step solution
(1) Silica gel adsorbs moisture
(2) True
(3) True. (Bonds weaken on the surface)
(4) True
(5) True (Chemisorption need activation energy.
(6) True, physisorption is due to weak attractive forces, hence it occurs little farther from surface atoms in comparison to chemisorption. Moreover the decrease in potential energy is more in chemisorption than in physisorption.