NEET 2025 MCQ with Answer Explanation : “Molecular Orbital Theory”.

81. What is the hybridization of the central atom in a molecule with a trigonal bipyramidal shape?
A) sp
B) sp²
C) sp³d
D) sp³d²

Answer: C

Explanation: The central atom in a trigonal bipyramidal geometry has sp³d hybridization.

82. Which of the following molecules has a bond angle of approximately 120°?
A) CH4
B) NH3
C) BCl3
D) H2O
Answer: C

Explanation: BCl3 has a trigonal planar structure with bond angles of approximately 120°.

83. Which molecular orbital theory describes the energy levels of bonding and antibonding orbitals?
A) Lewis Theory
B) Valence Shell Electron Pair Repulsion Theory
C) Molecular Orbital Theory
D) Crystal Field Theory
Answer: C

Explanation: Molecular Orbital Theory focuses on the energy levels and properties of bonding and antibonding molecular orbitals.

84. Which of the following molecules is expected to be paramagnetic?
A) Ne
B) O2
C) F2
D) He2

Answer: B

Explanation: O2 has unpaired electrons in its molecular orbital configuration, making it paramagnetic.

85. What is the molecular geometry of a molecule with sp³ hybridization?
A) Linear
B) Trigonal planar
C) Tetrahedral
D) Octahedral

Answer: C

Explanation: Molecules with sp³ hybridization adopt a tetrahedral geometry.

86. Which of the following correctly describes the bond order of F2?
A) 1
B) 2
C) 3
D) 4

Answer: A

Explanation: F2 has a bond order of 1, indicating a single bond between the two fluorine atoms.

87. Which of the following statements is true regarding π bonds?
A) They can only be formed by p orbitals.
B) They are stronger than sigma bonds.
C) They can be formed by the overlap of s and p orbitals.
D) They can exist independently of sigma bonds.

Answer: A

Explanation: π bonds are formed by the side-to-side overlap of p orbitals and cannot exist without a sigma bond.

88. Which molecular orbital is represented by the notation π?*
A) Bonding molecular orbital
B) Antibonding molecular orbital
C) Non-bonding molecular orbital
D) Both A and C

Answer: B

Explanation: The π* notation indicates an antibonding molecular orbital formed from p orbitals.

89. What is the bond order of a molecule with 4 bonding electrons and 2 antibonding electrons?
A) 0
B) 1
C) 2
D) 3

Answer: B

Explanation: Bond order = (number of bonding electrons – number of antibonding electrons) / 2 = (4 – 2) / 2 = 1.

90. In which molecular orbital are the electrons responsible for the bond in H2 located?
A) σ1s
B) σ*1s
C) π2p
D) σ2p

Answer: A

Explanation: In H2, the electrons are located in the bonding molecular orbital σ1s, which contributes to the bond formation.