Chemical Bonding and Molecular Structure

70 lessons, pages 1616–1685.

  1. Bonding Models at Higher Secondary Level — Comparing Lewis, valence-bond and molecular-orbital explanations
  2. Ionic Bond Formation and Energetics — Electron transfer, lattice stabilisation and why transfer alone is insufficient
  3. Born–Haber Cycle for Sodium Chloride — Accounting for atomisation, ionisation, affinity and lattice enthalpy
  4. Lattice Enthalpy Trends — Charge product, ionic separation and limitations of a simple Coulomb model
  5. Polarisation and Fajans' Rules — Cation polarising power and anion polarisability in ionic compounds
  6. Covalent Bond Formation and Orbital Overlap — Lower energy through electron density between two nuclei
  7. Sigma and Pi Bonding — Head-on and side-on overlap in single, double and triple bonds
  8. Bond Length, Strength and Potential Energy — Equilibrium separation and dissociation-energy comparisons
  9. Coordinate Bonding and Donor–Acceptor Pairs — Lone-pair donation in ammonium and Lewis acid–base adducts
  10. Lewis Electron Accounting for Ions — Valence-electron budgets with positive and negative charge
  11. Formal Charge Calculations — Nonbonding and half-bonding electron bookkeeping in Lewis forms
  12. Formal Charge and Preferred Structures — Evaluating charge separation without treating rules as absolute
  13. Resonance in Nitrate and Carbonate — Equivalent contributors and delocalised bond character
  14. Octet Exceptions and Expanded Valence — Electron-deficient and hypervalent structures with model limits
  15. VSEPR Electron Domains — Counting sigma-bond regions and lone pairs around a center
  16. Linear and Trigonal Planar Geometries — Two and three domains with ideal angles and double-bond effects
  17. Tetrahedral, Pyramidal and Bent Shapes — Four-domain molecules CH₄, NH₃ and H₂O compared
  18. Trigonal Bipyramidal Geometry — Axial and equatorial positions in five-domain molecules
  19. Five-Domain Lone-Pair Shapes — Seesaw, T-shaped and linear arrangements in SF₄, ClF₃ and XeF₂
  20. Octahedral and Square-Pyramidal Shapes — Six electron domains in SF₆ and BrF₅
  21. Square-Planar Molecular Shape — Opposed lone pairs and the XeF₄ example
  22. VSEPR Bond-Angle Deviations — Lone-pair and multiple-bond effects beyond ideal angles
  23. VSEPR Limits and Experimental Shapes — When simple domain repulsion is a qualitative model only
  24. Bond Dipoles and Electronegativity — Partial charges and vector direction of a polar bond
  25. Molecular Dipole Cancellation — Combining bond vectors in CO₂, H₂O, BF₃ and CCl₄
  26. Dipole Moment and Shape Problems — Using symmetry with three-dimensional geometry rather than formula alone
  27. Valence-Bond Theory and Localised Bonds — Atomic-orbital overlap, spin pairing and model scope
  28. Hybrid Orbitals as a Geometry Model — Mixing atomic orbitals conceptually without claiming literal motion
  29. sp Hybridisation and Linear Centers — Two sigma directions and unhybridised p orbitals
  30. sp² Hybridisation and Trigonal Centers — Three sigma directions and a remaining p orbital for pi bonding
  31. sp³ Hybridisation and Tetrahedral Centers — Four sigma directions in methane and local carbon bonding
  32. Hybridisation in Ethene and Ethyne — Relating carbon geometry to sigma and pi bond counts
  33. Hybridisation with Lone Pairs — Ammonia and water orbital labels versus observed molecular shapes
  34. Hypervalent Hybridisation Labels and Cautions — Traditional sp³d and sp³d² labels with modern model limitations
  35. Molecular-Orbital Theory as a Delocalised Model — Orbitals spanning molecules rather than one bond at a time
  36. Bonding and Antibonding Orbitals — Constructive and destructive combinations in a diatomic molecule
  37. MO Electron Filling Rules — Aufbau, Pauli and Hund rules applied to molecular orbitals
  38. Bond Order from MO Occupancy — Half the bonding-minus-antibonding electron count
  39. Hydrogen and Helium Diatomics — H₂, H₂⁺, He₂ and He₂⁺ bond-order comparisons
  40. Second-Period MO Energy Ordering — Why B₂–N₂ and O₂–F₂ use different 2p level orderings
  41. MO Diagram of Nitrogen — N₂ electron filling, bond order three and diamagnetism
  42. MO Diagram of Oxygen — O₂ antibonding pi electrons, bond order two and paramagnetism
  43. MO Predictions for Diatomic Ions — Electron removal or addition and consequent bond-order changes
  44. Magnetism from Unpaired Electrons — Paramagnetic versus diamagnetic molecules in MO theory
  45. Comparing Valence-Bond and MO Accounts — Local bond pictures versus delocalised orbitals for O₂ and N₂
  46. Intermolecular Forces in Molecular Substances — Dispersion, dipole interactions and hydrogen bonds as distinct effects
  47. London Dispersion and Polarisability — Electron-cloud fluctuations, size and molecular contact
  48. Permanent Dipole Interactions — Orientation-dependent attractions between polar molecules
  49. Hydrogen-Bond Donors and Acceptors — N–H, O–H or F–H donors and lone-pair acceptors in context
  50. Hydrogen Bonding in Water and HF — Directional intermolecular networks and their property effects
  51. Water Versus Hydrogen Sulfide — Comparing boiling behaviour from bonding and molecular size
  52. Intermolecular Versus Intramolecular Hydrogen Bonds — Competition between internal and between-molecule attractions
  53. Boiling and Solubility from Force Patterns — Using whole-molecule structure and avoiding single-force rankings
  54. Metallic and Network Bonding Revisited — Contrasting delocalised metals, covalent networks and molecules
  55. Bonding in Polyatomic Ionic Compounds — Covalent bonds within ions and electrostatics between ions
  56. Percent Ionic Character as a Continuum — Bond polarity without a sharp ionic–covalent dividing line
  57. Bond Enthalpy and Reaction Energy Estimates — Breaking and forming bonds with average enthalpy limitations
  58. Bond-Length and Bond-Order Comparisons — Using bond order trends while recognising chemical context
  59. Formal Charge and Resonance Problem Set — Electron-count and contributor analysis for several ions
  60. VSEPR Shape Problem Set — Electron geometry, molecular shape and lone-pair counting
  61. Hybridisation and Bond-Count Problem Set — Sigma/pi counts and local geometry in small molecules
  62. MO Bond-Order Problem Set — Occupancy, ion formation and magnetism of diatomics
  63. Polarity and Force Problem Set — Vector cancellation and intermolecular attraction together
  64. Bonding Model Error Clinic — Correcting octet, lone-pair, hybridisation and MO misconceptions
  65. Bonding Evidence from Properties — Using conductivity, melting and solubility as qualified clues
  66. Mixed Lewis-to-Shape Workflow — From formula and electron budget to geometry and polarity
  67. Integrated Ionic and Covalent Problems — Combining lattice, polarisation and molecular bonding ideas
  68. Integrated Molecular Structure Problems — Connecting formal charge, VSEPR, hybrid and dipole models
  69. Integrated MO and Intermolecular Problems — Bond order, magnetism and bulk-property distinctions
  70. Chemical Bonding and Molecular Structure Review — Choosing and checking models from Lewis structures to MO theory