{
  "version": "2026.05",
  "confidence": "classroom model",
  "families": [
    {
      "id": "strong-acid-base-neutralization",
      "title": "Strong acid/base neutralization",
      "netIonic": "H+(aq) + OH-(aq) -> H2O(l)",
      "visibleEvidence": ["temperature increase"],
      "calculation": "limiting reagent, enthalpy estimate, pH after excess H+ or OH-"
    },
    {
      "id": "weak-acid-base-buffer",
      "title": "Weak acid/base and buffer behavior",
      "examples": ["CH3COOH + OH- -> CH3COO- + H2O", "NH3 + H+ -> NH4+"],
      "visibleEvidence": ["pH trend", "indicator color"],
      "calculation": "Henderson-Hasselbalch when conjugate pair exists; square-root approximation otherwise"
    },
    {
      "id": "precipitation",
      "title": "Precipitation by Ksp and solubility rules",
      "examples": ["Ag+(aq) + Cl-(aq) -> AgCl(s)", "Ca2+(aq) + CO3^2-(aq) -> CaCO3(s)"],
      "visibleEvidence": ["cloudy solid", "settled precipitate"],
      "calculation": "limiting ion and precipitate mass"
    },
    {
      "id": "gas-evolution",
      "title": "Carbonate acid gas evolution",
      "examples": ["2 H+(aq) + CO3^2-(aq) -> CO2(g) + H2O(l)", "H+(aq) + HCO3-(aq) -> CO2(g) + H2O(l)"],
      "visibleEvidence": ["bubbles", "gas amount"],
      "calculation": "stoichiometric gas moles"
    },
    {
      "id": "simple-redox",
      "title": "Acidic permanganate oxidation of iron(II)",
      "netIonic": "MnO4-(aq) + 5 Fe2+(aq) + 8 H+(aq) -> Mn2+(aq) + 5 Fe3+(aq) + 4 H2O(l)",
      "visibleEvidence": ["purple color fades", "iron(III) color appears"],
      "calculation": "limiting reagent and species ledger"
    }
  ]
}