COMEDK 2025 Morning Solved Paper

Concept:VSEPR theory predicts molecular shape based on electron pair repulsion.Explanation:Option A: $\mathrm{CH}_4$ has $\mathrm{sp}^3$ hybridisation, but $\mathrm{SF}_4$ has $\mathrm{sp}^3\mathrm{d}$ hybridisation (see-saw shape).Thus, A is false.Option B: The dipole moment of $\mathrm{NH}_3$ ($\approx 1.47$ D) is greater than that of $\mathrm{NF}_3$ ($\approx 0.24$ D).In $\mathrm{NF}_3$, bond dipoles oppose the lone pair dipole, reducing net moment.Thus, B is false.Option C: The $\mathrm{C}-\mathrm{O}$ bond length in $\mathrm{CO}_2$ is about $116$ pm due to double bond character, not inductive effect.Oxygen exerts a $-\mathrm{I}$ effect, not $+\mathrm{I}$.Thus, C is false.Option D: A molecule of type $\mathrm{AB}_5\mathrm{E}$ (5 bond pairs and 1 lone pair) has octahedral electron geometry.The lone pair occupies an axial position, yielding a square pyramidal molecular shape.Thus, D is correct.Answer:D