When O₂ is adsorbed on a metallic surface, electron transfer occurs from the metal to O₂. The TRUE statement(s) regarding this adsorption is(are)
- (A)O₂ is physisorbed
- (B)heat is released✓ Correct
- (C)occupancy of π*₂ₚ of O₂ is increased✓ Correct
- (D)bond length of O₂ is increased✓ Correct
Answer: (B), (C), (D)
Solution
When O₂ is adsorbed on a metal surface with electron transfer:
(A) Electron transfer indicates chemical bonding (chemisorption), not physisorption. Incorrect.
(B) Adsorption is an exothermic process; heat is released. Correct.
(C) Electrons from the metal enter the antibonding π*₂ₚ orbitals of O₂, increasing their occupancy. Correct.
(D) Increased occupancy of antibonding orbitals weakens the O-O bond, increasing bond length. Correct.
Correct options: (B), (C) and (D).
(A) Electron transfer indicates chemical bonding (chemisorption), not physisorption. Incorrect.
(B) Adsorption is an exothermic process; heat is released. Correct.
(C) Electrons from the metal enter the antibonding π*₂ₚ orbitals of O₂, increasing their occupancy. Correct.
(D) Increased occupancy of antibonding orbitals weakens the O-O bond, increasing bond length. Correct.
Correct options: (B), (C) and (D).
JEE Advanced · 2015 · 24 May 2015 · Paper 2 · One or more correct options