Summary
This textbook section covers the core principles of gaseous chemical equilibrium, including how to write and interpret equilibrium constant expressions (K) and the reaction quotient (Q). It emphasizes the use of ICE tables to determine the pressures or concentrations at equilibrium and illustrates the predictive power of Le Châtelier’s principle in response to changes in reaction conditions such as pressure, volume, and temperature. The rules for modifying K when coefficients change (coefficient rule, reciprocal rule, and the rule for multiple equilibria) form the foundation for understanding equilibrium in both homogeneous and heterogeneous systems.