Given below are two statements:
Statement I: The number of species among SF₄$\mathrm{SF}_4$, NH₄^+$\mathrm{NH}_4^+$, [NiCl₄]²⁻$[\mathrm{NiCl}_4]^{2-}$, XeF₄$\mathrm{XeF}_4$, [PtCl₄]²⁻$[\mathrm{PtCl}_4]^{2-}$, SeF₄$\mathrm{SeF}_4$ and [Ni(CN)₄]²⁻$[\mathrm{Ni(CN)}_4]^{2-}$, that have tetrahedral geometry is 3.
Statement II: In the set [NO₂, BeH₂, BF₃, AlCl₃]$[NO_{2}, BeH_{2}, BF_{3}, AlCl_{3}]$, all the molecules have incomplete octet around central atom.
In the light of the above statements, choose the correct answer from the options given below:
A.Statement I is true but Statement II is false$\text{Statement I is true but Statement II is false}$
B.Both Statement I and Statement II are false$\text{Both Statement I and Statement II are false}$
C.Statement I is false but Statement II is true$\text{Statement I is false but Statement II is true}$
D.Both Statement I and Statement II are true$\text{Both Statement I and Statement II are true}$
Keywords:#tetrahedral geometry#incomplete octet#JEE Main 2026 Morning Q64#Chemical Bonding and Molecular Structure JEE Main 2026
More Chemical Bonding and Molecular Structure Previous-Year Questions
Q64jee_main_2026_21_jan_eveningBond Length Trends
The correct increasing order of C-H (A)$\text{C-H (A)}$, C-O (B)$\text{C-O (B)}$, C=O (C)$\text{C=O (C)}$ and C (D)$\text{C}\equiv\text{N (D)}$ bonds in terms of covalent bond length is:
(1) A < B < C < D$A < B < C < D$
(2) A < D < C < B$A < D < C < B$
(3) D < C < B < A$D < C < B < A$
(4) D < C < A < B$D < C < A < B$
A.(1) A < B < C < D$(1) \ A < B < C < D$
B.(2) A < D < C < B$(2) \ A < D < C < B$
C.(3) D < C < B < A$(3) \ D < C < B < A$
D.(4) D < C < A < B$(4) \ D < C < A < B$
Solution
Core Logic
Comparing bond lengths:
C–H (A): 107 pm$\sim 107 \text{ pm}$
C≡N (D): 116 pm$\sim 116 \text{ pm}$
C=O (C): 121 pm$\sim 121 \text{ pm}$
C–O (B): 143 pm$\sim 143 \text{ pm}$
Step 1: Final Conclusion
Thus, the increasing order is A < D < C < B$A < D < C < B$, corresponding to option (2).
Pattern Recognition
Sees: covalent bond length comparison across bond orders and atomic radii.
Trap: Assuming triple bonds are always longer or shorter without accounting for smaller atomic radii like hydrogen.
Chapter Mix
Class 11 Chemistry: Chemical Bonding and Molecular Structure
Q69jee_main_2026_21_jan_eveningBond Dissociation Enthalpy and Fajan's Rules
Given below are two statements:
Statement I: The correct order in terms of bond dissociation enthalpy is Cl₂ > Br₂ > F₂ > I₂$\text{Cl}_2 > \text{Br}_2 > \text{F}_2 > \text{I}_2$.
Statement II: The correct trend in the covalent character of the metal halides is [SnCl₄ > SnCl₂]$[\text{SnCl}_4 > \text{SnCl}_2]$, [PbCl₄ > PbCl₂]$[\text{PbCl}_4 > \text{PbCl}_2]$ and [UF₄ > UF₆]$[\text{UF}_4 > \text{UF}_6]$ (or similar Fajan's rule trend).
In the light of the above statements, choose the correct answer from the options given below:
A.(1) Statement I is true but Statement II is false$(1) \text{ Statement I is true but Statement II is false}$
B.(2) Both Statement I and Statement II are true$(2) \text{ Both Statement I and Statement II are true}$
C.(3) Statement I is false but Statement II is true$(3) \text{ Statement I is false but Statement II is true}$
D.(4) Both Statement I and Statement II are false$(4) \text{ Both Statement I and Statement II are false}$
Solution
Core Logic
Statement I: Bond dissociation energy order for halogens is Cl₂ > Br₂ > F₂ > I₂$\text{Cl}_2 > \text{Br}_2 > \text{F}_2 > \text{I}_2$ 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$\text{UF}_6 > \text{UF}_4$ (higher oxidation state has greater covalent character), making the statement II claim regarding UF₄ > UF₆$\text{UF}_4 > \text{UF}_6$ 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
Q52jee_main_2026_22_january_morningLewis Structures and Formal Charge
The formal changes on the atoms marked as (1) to (4) in the Lewis representation of HNO₃$HNO_{3}$ molecule respectively are
The image shows the Lewis structure of HNO3 with four atoms numbered 1 through 4.
The formal charges on atoms (1), (2), (3), and (4) are respectively 0, +1, 0, -1.
Pattern Recognition
In nitro groups (-NO₂$-NO_2$), the central nitrogen is always +1, the single bonded oxygen is -1, and the double-bonded oxygen is 0.
Chapter Mix
Class 11 Chemistry: Chemical Bonding and Molecular Structure
Q68jee_main_2026_22_january_morningHybridization and VSEPR Theory
Two p-block elements X and Y form fluroides of the type EF₃$EF_{3}$. The fluoride compound XF₃$XF_{3}$ is a Lewis acid and YF₃$YF_{3}$ is a Lewis base. The hybridization of the central atoms of XF₃$XF_{3}$ and YF₃$YF_{3}$ respectively are
A.Both sp³$\text{Both } sp^{3}$
B.sp² and sp³$sp^{2} \text{ and } sp^{3}$
C.sp³ and sp²$sp^{3} \text{ and } sp^{2}$
D.Both sp²$\text{Both } sp^{2}$
Solution
Core Logic
XF₃$XF_3$ acts as a Lewis acid, meaning it is an electron-deficient species capable of accepting an electron pair. A common example from the p-block is BF₃$BF_3$. The central Boron atom has 3 bond pairs and 0 lone pairs. Therefore, its steric number is 3, corresponding to sp²$sp^2$ hybridization.
YF₃$YF_3$ acts as a Lewis base, meaning it has an available lone pair to donate. A common example is NF₃$NF_3$. The central Nitrogen atom has 3 bond pairs and 1 lone pair. Its steric number is 4, corresponding to sp³$sp^3$ hybridization.
Step 1: Final Conclusion
The hybridization of X and Y respectively are sp²$sp^2$ and sp³$sp^3$.
Pattern Recognition
Electron deficient central atoms (Group 13) form sp²$sp^2$ planar molecules. Atoms with a lone pair (Group 15) form sp³$sp^3$ pyramidal molecules.
Chapter Mix
Class 11 Chemistry: Chemical Bonding and Molecular Structure
Class 11 Chemistry: p-Block Elements
More Chemical Bonding and Molecular Structure Questions — jee_main_2026_21_jan_morning
Practice past-year questions one chapter at a time. Pick an exam → subject → chapter and get every PYQ for that topic — pulled together from all past papers — with the chapter's key formulas alongside.