JEE Main202621 January 2026Morning ShiftChemistryChemical Bonding and Molecular StructureActual
Given below are two statements : Statement I : The number of species among SF ₄, NH ₄⁺, [ NiCl ₄ ]²⁻, XeF ₄, [ PtCl ₄ ]²⁻, SeF ₄ and [ Ni ( CN )₄ ]²⁻ , that have tetrahedral geometry is 3. Statement II : In the set [ 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 :
Options
- AStatement I is true but Statement II is false
- BStatement I is false but Statement II is true
- CBoth Statement I and Statement II are true
- DBoth Statement I and Statement II are false
Correct answer
B. Statement I is false but Statement II is true
Step-by-step solution
Statement I: Checking geometry of each species: SF₄ : 4 bp + 1 lp → see-saw NH₄^+ : 4 bp → tetrahedral [NiCl₄]²⁻ : Ni²⁺ (d⁸) with weak field Cl^- → sp^3 → tetrahedral XeF₄ : 4 bp + 2 lp → square planar [PtCl₄]²⁻ : Pt²⁺ (d⁸) → dsp^2 → square planar SeF₄ : 4 bp + 1 lp → see-saw [Ni(CN)₄]²⁻ : Ni²⁺ with strong field CN^- → dsp^2 → square planar Only 2 species are tetrahedral. Statement I is false. Statement II: NO₂ (odd electron), BeH₂ (4e⁻), BF₃ (6e⁻), AlCl₃ (6e⁻) all have incomplete octet. Statement II is true.