Bonding and Lewis Structures

60 lessons, pages 1021–1080.

  1. Why Atoms Form Chemical Bonds — Lower-energy arrangements and attraction balanced against repulsion
  2. Valence Electrons and Lewis Symbols — Representing outer electrons without claiming fixed positions
  3. The Octet Rule and Its Scope — Useful main-group pattern, hydrogen duet and important exceptions
  4. Ionic Bonding and Charge Balance — Cation–anion attraction and electrically neutral formula units
  5. Predicting Simple Ion Charges — Using groups, electron loss or gain and chemical context
  6. Formulas Containing Polyatomic Ions — Balancing whole-ion charges and using parentheses correctly
  7. Ionic Lattices and Formula Units — Three-dimensional electrostatic networks rather than discrete pairs
  8. Lattice Energy as a Bonding Measure — Qualitative effects of ion charge and separation
  9. Explaining Ionic Substance Properties — Melting, brittleness and conductivity from moving charges
  10. Covalent Bonds as Shared Electron Density — Electron sharing, orbital overlap and attraction between nuclei
  11. Lewis Structures: Symbols and Conventions — Bonds, lone pairs, brackets and charges on two-dimensional drawings
  12. Counting Valence Electrons for Lewis Structures — Electron totals for neutral molecules, cations and anions
  13. Choosing a Lewis Skeleton — Connectivity, central atoms and special treatment of hydrogen
  14. Placing Bonds and Lone Pairs — Allocating an electron budget to terminal and central atoms
  15. When Lewis Structures Need Multiple Bonds — Moving lone pairs to form double or triple bonds
  16. Checking Lewis Structures Systematically — Recounting electrons, octets, charge and plausible connectivity
  17. Formal Charge in Lewis Diagrams — Bookkeeping formula and distinction from measured atomic charge
  18. Comparing Plausible Lewis Diagrams — Formal-charge patterns, electronegativity and structural evidence
  19. Resonance and Delocalised Electrons — Alternative contributing diagrams for one connected species
  20. Resonance Is Not Molecular Switching — Distinguishing resonance contributors from isomers and equilibrium
  21. Electron-Deficient Lewis Structures — Boron and beryllium examples that lack an octet
  22. Odd-Electron Molecules and Radicals — Recognising an unpaired electron in a valence count
  23. Expanded-Valence Lewis Drawings — Useful hypervalent representations and limits of the octet model
  24. Hydrogen and Hydrogen Chloride Lewis Diagrams — A duet, one bonding pair and differing bond polarity
  25. Water and Ammonia Lewis Diagrams — Counting bonds and lone pairs around oxygen and nitrogen
  26. Methane and Carbon's Four Bonds — Drawing CH4 and distinguishing formula from spatial shape
  27. Oxygen and Nitrogen Multiple Bonds — Lewis double and triple bonds with remaining lone pairs
  28. Carbon Dioxide and Double-Bond Counting — Constructing O=C=O from sixteen valence electrons
  29. Ethene and Ethyne as Lewis Examples — Single, double and triple bonding in small hydrocarbons
  30. Nitrate Ion and Equivalent Bonds — Resonance contributors, formal charges and bond equivalence
  31. Carbonate Ion and Resonance — Three contributing diagrams and distributed negative charge
  32. Ammonium and Hydronium Ions — Lewis electron counts and the origin of a coordinate bond
  33. Coordinate Covalent Bonding — Electron-pair donation without a different final bond type
  34. Sulfur Oxyanion Lewis Models — Electron counting, formal charge and model-dependent depictions
  35. Bond Order, Bond Length and Strength — Broad relationships and why comparisons need like-for-like bonds
  36. Bond Enthalpy and Bond Breaking — Positive gas-phase dissociation energy and approximate reaction estimates
  37. Bonding Pairs and Lone Pairs — Electron domains and their influence on local geometry
  38. Electron-Domain Repulsion Model — Predicting simple shapes while recognising model limitations
  39. Linear and Trigonal Planar Shapes — Two and three electron domains around a central atom
  40. Tetrahedral Electron Arrangements — Four electron domains and the ideal tetrahedral angle
  41. Pyramidal and Bent Molecules — Lone pairs distinguish ammonia and water from methane
  42. Multiple Bonds in Shape Predictions — One electron domain per multiple-bond region in basic VSEPR
  43. Electronegativity and Polar Bonds — Unequal electron sharing and partial charges
  44. Bond Dipole Direction — Representing bond polarity without confusing it with ionic charge
  45. Molecular Polarity and Geometry — Combining bond dipoles as vectors in three dimensions
  46. Carbon Dioxide Versus Water Polarity — Why polar bonds can cancel or reinforce depending on shape
  47. Ionic and Covalent Bonding as Models — A continuum of electron distribution rather than a rigid boundary
  48. Polarisation in Ionic Compounds — How cation charge density and anion size affect covalent character
  49. Metallic Bonding and Mobile Electrons — Lattice cohesion, electrical conduction and ductility
  50. Giant Covalent Networks — Diamond, graphite and silica as structure-dependent materials
  51. Molecular Substances and Particle Attractions — Separating bonds within molecules from forces between molecules
  52. Comparing Intermolecular Forces — Dispersion, permanent dipoles and hydrogen bonding in context
  53. Hydrogen Bonding in Water — Directional attraction involving H bonded to N, O or F
  54. Linking Bonding to Bulk Properties — Using particle structure to explain melting and conductivity
  55. Formula, Lewis Diagram and Real Structure — What each representation shows and omits
  56. Bonding in Mixed Ionic–Covalent Substances — Polyatomic ions within ionic lattices
  57. Using Evidence to Infer Bonding — Conductivity, melting behaviour and solubility as qualified clues
  58. Mixed Lewis and Formal-Charge Problems — Integrating valence counts, connectivity and charge checks
  59. Assessing Bonding Model Limits — Where Lewis, octet, ionic and simple shape models need refinement
  60. Bonding and Lewis Structures: Unit Review — Charge balance, electron counting, geometry and polarity together