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Chemical Bonding and Molecular Structure appeared 42 times across 3 years — 4.9% of Chemistry. This question is from Molecular Geometry and VSEPR.

Year 2026 2025 2024 Total
Questions 12 14 16 42

The molecules having square pyramidal geometry are

Solution & Explanation

Core Logic

Let us check the steric details using VSEPR theory:

  • BrF₅: Bromine has 7 valence electrons. It forms 5 single bonds with Fluorine and retains 1 lone pair. Steric number = 6 (sp³d²), geometry is square pyramidal.
  • XeOF₄: Xenon has 8 valence electrons. It forms 1 double bond with Oxygen, 4 single bonds with Fluorine, and retains 1 lone pair. Steric number = 6 (sp³d²), geometry is square pyramidal.
  • SbF₅ & PCl₅: Central element has 5 valence electrons, forming 5 bonds with no lone pairs. Steric number = 5 (sp³d), geometry is trigonal bipyramidal.
  • Visual representations of geometries:

    Geometry structure diagram 1 for Q35 - JEE Main 2025 Morning
    Geometry structure diagram 1 for Q35 - JEE Main 2025 Morning
    Geometry structure diagram 1 for Q35 - JEE Main 2025 Morning
    Geometry structure diagram 1 for Q35 - JEE Main 2025 Morning
    Geometry structure diagram 1 for Q35 - JEE Main 2025 Morning
    Geometry structure diagram 1 for Q35 - JEE Main 2025 Morning
    Geometry structure diagram 1 for Q35 - JEE Main 2025 Morning
    Geometry structure diagram 1 for Q35 - JEE Main 2025 Morning

Pattern Recognition

Sees: Steric count 6 with 5 bonded segments + 1 lone pair arrow always square pyramidal geometry.

Chapter Mix

Class 11 Chemistry: Chemical Bonding and Molecular Structure

Reference Study Guides

More Chemical Bonding and Molecular Structure Previous-Year Questions — Page 5

Q jee_main_2025_04_april_evening VSEPR Theory
Given below are two statements: Statement (I) : for C F₃ , all three possible structures may be drawn as follows.
ClF3 structure variant I for Q44
The prompt displays three configurations of chlorine trifluoride with differing spatial positions for its two lone electron pairs.
ClF3 structure variant I for Q44
The prompt displays three configurations of chlorine trifluoride with differing spatial positions for its two lone electron pairs.
ClF3 structure variant I for Q44
The prompt displays three configurations of chlorine trifluoride with differing spatial positions for its two lone electron pairs.
Statement (II) : Structure III is most stable, as the orbitals having the lone pairs are axial, where the p- bp repulsion is minimum. In the light of the above statements, choose the most appropriate answer from the options given below:
ClF3 structure variant I for Q44
The prompt displays three configurations of chlorine trifluoride with differing spatial positions for its two lone electron pairs.
  • A. Statement I is incorrect but statement II is correct.
  • B. Statement I is correct but statement II is incorrect.
  • C. Both Statement I and statement II are correct.
  • D. Both Statement I and statement II are incorrect.

Solution

Related Formula
Steric Number for ClF₃ = (7+3)/(2) = 5 sp³d hybridization (Trigonal Bipyramidal geometry)
Core Logic
  • Statement I is correct: The three structural arrangements represent the different ways to place three bond pairs and two lone pairs within a trigonal bipyramidal grid.
  • Statement II is incorrect: According to VSEPR theory and Bent's rule, in sp³d hybridization, lone pairs must occupy equatorial positions to minimize strong 90^° lone pair-bond pair (p-bp) repulsions. Placing them axially maximizes repulsions, making that structure the least stable, not the most stable.
Pattern Recognition

For sp³d configurations (Trigonal Bipyramidal), lone pairs ALWAYS prefer equatorial sites where they experience 120^circ interactions, minimizing severe 90^circ structural strains. This results in the classic stable T-shaped configuration for ClF₃.

Chapter Mix

Class 11 Chemistry: Chemical Bonding and Molecular Structure

Q28 jee_main_2025_04_april_morning Molecular Orbital Theory
Which of the following molecules(s) show/s paramagnetic behavior? (A) O₂ (B) N₂ (C) F₂ (D) S₂ (E) Cl₂ Choose the correct answer from the options given below:
  • A. B only
  • B. A & C only
  • C. A & E only
  • D. A & D only

Solution

Related Formula

Paramagnetism Presence of at least one unpaired electron in the molecular orbitals.

Core Logic

According to Molecular Orbital Theory (MOT):

  • O₂ has 16 electrons. Its outer configuration contains two unpaired electrons in the anti-bonding orbitals: π2pₓ = π2py. Thus, it is paramagnetic.
  • S₂ belongs to the same oxygen family group and shares an analogous valence configuration with two unpaired electrons in its anti-bonding π^* orbitals. Hence, it is also paramagnetic.
  • N₂ (14e-), F₂ (18e-), and Cl₂ (34e-) have completely paired electronic systems and behave diamagnetically.
Pattern Recognition

Both O₂ and S₂ contain 2 unpaired electrons in their highest occupied molecular orbitals, making them classic examples of paramagnetic diatomic species.

Chapter Mix

Class 11 Chemistry: Chemical Bonding and Molecular Structure

Q39 jee_main_2025_07_april_evening Hybridization
In SO₂, NO₂^- and N₃^- the hybridizations at the central atom are respectively:
  • A. sp², sp² and sp
  • B. sp², sp and sp
  • C. sp², sp² and sp²
  • D. sp, sp² and sp

Solution

Related Formula
Steric Number (Steric count) = Number of lone pairs on central atom + Number of σ-bonds
Core Logic

Let's perform steric calculations for each species:

  • SO₂: Central sulfur atom has 6 valence electrons, forms 2 σ-bonds (and 2 π-bonds) with oxygen, leaving 1 lone pair. Steric number = 2 + 1 = 3 sp².
  • NO₂^-: Central nitrogen atom has 5 valence electrons + 1 from negative charge = 6. It forms 2 σ-bonds, leaving 1 lone pair. Steric number = 2 + 1 = 3 sp².
  • N₃^- (Azide ion): Linear configuration structure can be drawn as:
N= +N= N

The central nitrogen has 2 σ-bonds and 0 lone pairs. Steric number = 2 + 0 = 2 sp.

Step 1: Geometry Outlines

The individual orbital fields are represented visually:

Hybridization diagram for Q39 - JEE Main 2025 Evening
Hybridization diagram for Q39 - JEE Main 2025 Evening

Hence, hybridizations follow the order: sp², sp², and sp.

Pattern Recognition

Steric short tracking: Species with linear structures like CO₂, N₂O, N₃^- possess central atoms that are always sp hybridized due to the requirement of two opposing σ-bonds.

Chapter Mix

Class 11 Chemistry: Chemical Bonding and Molecular Structure

Q32 jee_main_2025_24_jan_evening Resonance and Bond Parameters
Given below are two statements: Statement (I) : Experimentally determined oxygen-oxygen bond lengths in the O₃ are found to be same and the bond length is greater than that of a O=O (double bond) but less than that of a single (O-O) bond. Statement (II) : The strong lone pair-lone pair repulsion between oxygen atoms is solely responsible for the fact that the bond length in ozone is smaller than that of a double bond (O=O) but more than that of a single bond (O-O). In the light of the above statements, choose the correct answer from the options given below:
  • A. \text{Statement I is true but Statement II is false}
  • B. \text{Both Statement I and Statement II are true}
  • C. \text{Both Statement I and Statement II are false}
  • D. \text{Statement I is false but Statement II is true}

Solution

Core Logic

Analysis of Statement I: Ozone (O₃) exhibits resonance. The two major canonical forms contribute equally to the resonance hybrid, meaning both oxygen-oxygen bonds are identical. Their bond order is 1.5, making the bond length intermediate between a true single bond and a true double bond. Thus, Statement I is completely true.

Analysis of Statement II: Statement II claims that lone pair-lone pair repulsion is solely responsible for this intermediate bond length. This is incorrect. The intermediate bond parameter is fundamentally a direct consequence of resonance delocalization, not lone-pair repulsions. Thus, Statement II is false.

Pattern Recognition

Whenever a molecule has identical intermediate bond lengths instead of distinct single and double bonds, resonance delocalization is almost always the core underlying reason.

Chapter Mix

Class 11 Chemistry: Chemical Bonding and Molecular Structure

Q30 jee_main_2025_24_jan_morning Molecular Orbital Theory
Which of the following linear combination of atomic orbitals will lead to formation of molecular orbitals in homonuclear diatomic molecules [internuclear axis in z-direction]? A. 2pz and 2pₓ B. 2s and 2pₓ C. 3dxy and 3dx²-y² D. 2s and 2pz E. 2pz and 3dx²-y² Choose the correct answer from the options given below:
  • A. E Only
  • B. A and B Only
  • C. D Only
  • D. C and D Only

Solution

Core Logic

For atomic orbitals to successfully combine into molecular orbitals, they must share appropriate spatial symmetry relative to the internuclear axis (z-axis).

  • Combination A, B, C, and E involve orbitals with mismatching symmetry planes, resulting in a net zero overlap integral.
  • Combination D (2s and 2pz) preserves continuous spatial alignment along the z-axis, allowing effective frontal overlap to synthesize a stable sigma molecular orbital.
  • Visual symmetry breakdowns:

  • Molecular Orbital Theory diagram 1 for Q30
    Molecular Orbital Theory diagram 1 for Q30
    (Symmetry mismatch for A)
  • Molecular Orbital Theory diagram 1 for Q30
    Molecular Orbital Theory diagram 1 for Q30
    (Symmetry mismatch for C)
  • Molecular Orbital Theory diagram 1 for Q30
    Molecular Orbital Theory diagram 1 for Q30
    (Valid overlapping leading to Sigma molecular orbital for D)
  • Molecular Orbital Theory diagram 1 for Q30
    Molecular Orbital Theory diagram 1 for Q30
    (Symmetry mismatch for E)
Pattern Recognition

Verify orbital symmetry signs across the designated internuclear reference line. Mismatched symmetries cancel out completely (Ioverlap = 0).

Chapter Mix

Class 11 Chemistry: Chemical Bonding and Molecular Structure

More Chemical Bonding and Molecular Structure Questions — jee_main_2025_28_jan_morning

Practice all Chemical Bonding and Molecular Structure previous-year questions →

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JEE Physics: Waves (+15.5%) | Electrostatics: Concentric Shells (-29.7%) | Modern Physics: Photoelectric Clones (+34.2%) | Mathematics: Definite Integrals (+18.1%) | Chemistry: Coordination Splitting (-11.4%) | JEE Physics: Waves (+15.5%) | Electrostatics: Concentric Shells (-29.7%) | Modern Physics: Photoelectric Clones (+34.2%) | Mathematics: Definite Integrals (+18.1%) | Chemistry: Coordination Splitting (-11.4%)