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Chemical Bonding and Molecular Structure appeared 42 times across 3 years — 4.9% of Chemistry. This question is from Bond Dissociation Enthalpy and Fajan's Rules.

Year 2026 2025 2024 Total
Questions 12 14 16 42

Given below are two statements: Statement I: The correct order in terms of bond dissociation enthalpy is Cl₂ > Br₂ > F₂ > I₂. Statement II: The correct trend in the covalent character of the metal halides is [SnCl₄ > SnCl₂], [PbCl₄ > PbCl₂] and [UF₄ > UF₆] (or similar Fajan's rule trend). In the light of the above statements, choose the correct answer from the options given below:

Solution & Explanation

Core Logic
  • Statement I: Bond dissociation energy order for halogens is Cl₂ > Br₂ > F₂ > I₂ due to small size and lone-pair repulsions in fluorine weakening its bond. Statement I is true.
  • Statement II: According to Fajan's rules, higher charge on cation increases covalent character, so UF₆ > UF₄ (higher oxidation state has greater covalent character), making the statement II claim regarding UF₄ > UF₆ false.
Step 1: Final Conclusion

Statement I is true but Statement II is false, corresponding to option (1).

Pattern Recognition

Sees: halogen bond dissociation energy anomalies and Fajan's rules for covalent character. Trap: Assuming fluorine has the highest bond dissociation energy among halogens.

Chapter Mix

Class 11 Chemistry: Chemical Bonding and Molecular Structure

Reference Study Guides

More Chemical Bonding and Molecular Structure Previous-Year Questions — Page 9

Q77 jee_main_2024_31_jan_morning Molecular Orbital Theory
The linear combination of atomic orbitals to form molecular orbitals takes place only when the combining atomic orbitals A. have the same energy B. have the minimum overlap C. have same symmetry about the molecular axis D. have different symmetry about the molecular axis Choose the most appropriate from the options given below:
  • A. A, B, C only
  • B. A and C only
  • C. B, C, D only
  • D. B and D only

Solution

Core Logic

Conditions for the linear combination of atomic orbitals (LCAO) to form molecular orbitals:

  • The combining atomic orbitals must have the same or nearly the same energy.
  • The combining atomic orbitals must have the same symmetry about the molecular axis.
  • The combining atomic orbitals must overlap to the maximum extent (not minimum).
Chapter Mix

Class 11 Chemistry: Chemical Bonding and Molecular Structure

Q85 jee_main_2024_31_jan_morning Hybridization
The number of species from the following in which the central atom uses sp³ hybrid orbitals in its bonding is NH₃, SO₂, SiO₂, BeCl₂, CO₂, H₂O, CH₄, BF₃
Numerical Answer. Answer: 4 to 4

Solution

Core Logic

Analyzing the hybridization of the central atom in each species:

  • NH₃: 3 bp + 1 lp = 4 electron domains arrow sp³
  • SO₂: 2 bp + 1 lp = 3 electron domains arrow sp²
  • SiO₂: A giant covalent network where each Si is bonded to 4 oxygens tetrahedrally arrow sp³
  • BeCl₂: 2 bp + 0 lp = 2 electron domains arrow sp
  • CO₂: 2 bp + 0 lp = 2 electron domains arrow sp
  • H₂O: 2 bp + 2 lp = 4 electron domains arrow sp³
  • CH₄: 4 bp + 0 lp = 4 electron domains arrow sp³
  • BF₃: 3 bp + 0 lp = 3 electron domains arrow sp²
  • Total species with sp³ hybridization: NH₃, SiO₂, H₂O, CH₄. Total count = 4.

Chapter Mix

Class 11 Chemistry: Chemical Bonding and Molecular Structure

More Chemical Bonding and Molecular Structure Questions — jee_main_2026_21_jan_evening

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

Rankbit System
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%)