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Exam Questions Section A (1–16 MCQs, 1 mark each) (B) CO₂ (B) Osmotic pressure (D) Volume (C) NH₃ (D) 104.5° (B) Oxidizing properties (B) Prominent oxidation state (B) Electromeric effect (C) Both alkenes and alkynes (C) Intermolecular dipole-dipole interaction (B) Salicylaldehyde (C) Gem-dialkoxy compounds (B) Aniline (D) Globular proteins (D) Thermoplastic (A) Soap Section B (17–43) 17. Fill in the blanks (2 marks): Molar mass of NaCl. C-12 isotope. 1 mm = 0.001 m. Integral multiple. 18. VSEPR Theory (2 marks): Arrange to minimize repulsion. Bond angles link to repulsion. Trigonal bipyramidal for five pairs. Lone pairs are unbonded electrons. 19. True (T) or False (F) (2 marks): T T T T 20. True (T) or False (F): F T F T 21. True (T) or False (F): T F T T 22. True (T) or False (F): T T T F 23. True (T) or False (F): T F T T 24. Coordination Compounds (2 marks): Ligand field strength differs (CN⁻ > F⁻). Use AgNO₃ to differentiate. Example: EDTA. Bidentate ligand: en. 25. Ethers (2 marks): Geometry: Bent. React with HCl to form oxonium ions. IUPAC: Methoxypropane. Williamson’s synthesis: Alkyl halide + Alkoxide. 26. Nitro Compounds (2 marks): IUPAC: 2-Nitro-2-methylpentane. Propane + HNO₃ → Nitropropane. Nitrobenzene in alkaline medium gives aniline. Higher boiling points due to polarity. 27. Hormones and Vitamins (2 marks): Estrogen: Reproductive processes. Diabetes, pancreas. B₂: Cracked lips; B₉: Anemia. Fat-soluble: A and D. 28. Polymers (2 marks): Monomers: Terephthalic acid, ethylene glycol. Buna-S is a copolymer. Condensation gives by-products. Classified as linear, branched, or cross-linked. 29. Calculations (2 marks): Na₃PO₄ mass: 39.15 g. Empirical formula: CO₂. 30. d-Orbitals (2 marks): Shapes: dᶻ², dₓ²₋y², dₓy, dₓz, dᵧz. 31. Bonding (2 marks): Coordinate bond: Shared electron pair (e.g., NH₃ → BF₃). Bond angles: NH₃ = 107° CH₄ = 109.5° 32. Exothermic Reactions (2 marks): Definition: Release heat. Example: Combustion of CH₄. 33. Ionic Product (2 marks): Ionic product of water: [H⁺][OH⁻] = 10⁻¹⁴. 34. Electrolysis (2 marks): CuSO₄ electrolysis with Pt electrodes: Cu²⁺ → Cu (cathode); O₂ at anode. 35. Xenon Oxofluorides (2 marks): Xe reacts with F₂ under heat/pressure. 36. Dichromate Formation (2 marks): Na₂CrO₄ + H⁺ → Na₂Cr₂O₇ + H₂O. 37. Saytzeff’s Rule (2 marks): Major product: More substituted alkene (e.g., 2-butene from 2-butanol). 38. Methane Geometry (3 marks): Shape: Tetrahedral, as per VSEPR. 39. Internal Energy (3 marks): ΔU = +10 kJ. ΔU = -10 kJ. 40. Coordination Chemistry (3 marks): Formula: [Co(H₂O)₆]³⁺; inner orbital complex = d²sp³ hybridization. Hexacyanoferrate(III): Low spin; hexafluoroferrate(III): High spin. 41. Carbonyl Compounds (3 marks): Aldehydes more reactive due to less steric hindrance. Most acidic: 2-Chlorobutanoic acid. Tollen’s test: Silver mirror test for aldehydes. 42. Colligative Properties (5 marks): Freezing point: -0.12°C. CaCl₂: 0.93 g needed for osmotic pressure. 43. Periodic Trends (5 marks): Covalent character: SiCl₄ > SnCl₄ > Ge

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