“Valence Bond Theory” MCQ with Answer Explanation : NEET 2025.

31. Which of the following has sp hybridization in the central atom?
    A. CH₄
    B. CO₂
    C. NH₃
    D. H₂O

Answer: B. CO₂

Explanation: The carbon atom in CO₂ is sp hybridized, resulting in a linear structure with bond angles of 180°.

32. In VBT, the term hybridization refers to:
    A. The mixing of atomic orbitals to form new, equivalent orbitals
    B. The sharing of electrons in molecular orbitals
    C. The transfer of electrons between atoms
    D. The formation of ionic bonds

Answer: A. The mixing of atomic orbitals to form new, equivalent orbitals

Explanation: Hybridization is the process where atomic orbitals mix to form new hybrid orbitals that are degenerate (equal in energy) and participate in bonding.

33. Which of the following molecules involves sp³ hybridization?
    A. BeCl₂
    B. BF₃
    C. H₂O
    D. C₂H₂

Answer: C. H₂O

Explanation: In water (H₂O), oxygen undergoes sp³ hybridization, resulting in a bent molecular geometry due to the presence of two lone pairs.

34. The shape of a molecule of NH₄⁺ is:
    A. Trigonal planar
    B. Linear
    C. Tetrahedral
    D. Square planar

Answer: C. Tetrahedral

Explanation: In NH₄⁺ (ammonium ion), nitrogen is sp³ hybridized, forming a tetrahedral structure with bond angles of 109.5°.

35. According to VBT, the bond angle in ammonia (NH₃) is approximately:
    A. 90°
    B. 107°
    C. 120°
    D. 180°

Answer: B. 107°

Explanation: In ammonia, nitrogen undergoes sp³ hybridization. The presence of a lone pair compresses the bond angle from the ideal tetrahedral angle of 109.5° to about 107°.

36. Which of the following molecules has no hybridization involved in its bonding?
    A. N₂
    B. H₂O
    C. CH₄
    D. NH₃

Answer: A. N₂

Explanation: The nitrogen molecule (N₂) involves a triple bond between two nitrogen atoms, with no need for hybridization since only p-orbital overlap is required for the bonding.

37. In the molecule of BCl₃, boron is:
    A. sp hybridized
    B. sp² hybridized
    C. sp³ hybridized
    D. sp³d hybridized

Answer: B. sp² hybridized

Explanation: In boron trichloride (BCl₃), boron is sp² hybridized, leading to a trigonal planar structure with bond angles of 120°.

38. According to VBT, multiple bonds (double or triple bonds) involve:
    A. Only sigma bonds
    B. Only pi bonds
    C. One sigma bond and additional pi bonds
    D. Two sigma bonds

Answer: C. One sigma bond and additional pi bonds

Explanation: Multiple bonds consist of one sigma bond (due to head-on overlap) and one or more pi bonds (due to side-on overlap of p-orbitals).

39. Which of the following molecules involves sp³d² hybridization?
    A. SF₆
    B. PCl₅
    C. BF₃
    D. CO₂

Answer: A. SF₆

Explanation: In sulfur hexafluoride (SF₆), sulfur undergoes sp³d² hybridization, resulting in an octahedral molecular geometry with 90° bond angles.

40. The shape of a molecule of XeF₂ can be explained by which hybridization?
    A. sp
    B. sp²
    C. sp³d
    D. sp³d²

Answer: C. sp³d

Explanation: In xenon difluoride (XeF₂), xenon undergoes sp³d hybridization, resulting in a linear structure due to the presence of three lone pairs on xenon.