Which species acts as Lewis acid? A. NH₃ B. H₂O C. BF₃ D. OH⁻ Explanation: BF₃ accepts electron pair.
Which complex exhibits highest crystal field splitting? A. Tetrahedral B. Octahedral C. Square planar D. Linear Explanation: Square planar has largest splitting in many cases.
Which orbital penetrates closest to nucleus? A. 3p B. 3d C. 3s D. 4f Explanation: s orbitals have highest penetration.
The Gibbs phase rule is given by: A. F = C + P + 2 B. F = C − P + 2 C. F = P − C + 2 D. F = C − P − 2 Explanation: Degrees of freedom depend on components and phases.
The uncertainty in position and momentum obeys: A. Exact equality always B. Inequality relation C. Zero uncertainty D. Independent variables Explanation: Position and momentum uncertainties are fundamentally constrained.
Which tensor describes spacetime curvature? A. Maxwell tensor B. Riemann tensor C. Stress tensor D. Metric tensor only Explanation: Riemann curvature tensor quantifies spacetime curvature.
Which interaction violates parity symmetry? A. Strong B. Electromagnetic C. Weak D. Gravitational Explanation: Weak interaction is not symmetric under spatial inversion.
The work function of a metal is the minimum energy required to: A. Move electrons inside metal B. Remove an electron from surface C. Excite nucleus D. Ionize gas Explanation: Work function is threshold energy for electron emission.
Which phenomenon cannot be explained by classical physics? A. Reflection B. Refraction C. Blackbody radiation spectrum D. Sound waves Explanation: Classical theory fails to explain ultraviolet catastrophe.
The Planck constant has dimensions of: A. Energy B. Momentum C. Action D. Force Explanation: Planck constant has units of energy × time (action).