01What K tells you
K ≫ 1: products favored at equilibrium. K ≪ 1: reactants favored. K ≈ 1: comparable amounts.
K says nothing about speed.
02Notebook box
K = 1010 → essentially complete. K = 10^−10 → barely happens.
Worked example: Ksp of AgCl = 1.8 × 10^−10 → very little dissolves.