Assess students' understanding of chemical equilibrium and Le Chatelier’s principle for reversible reactions: define dynamic equilibrium, write and interpret equilibrium expressions (Kc, Kp), perform equilibrium concentration calculations from initial conditions, and predict qualitative shifts when concentration, pressure, or temperature change; include explanations of how perturbations affect reaction rates and K values. Suitable for Grade 9–12, medium difficulty, mix of quantitative problems and scenario-based reasoning.