General Solution for Equilibria Problems

Introduction

Use the following steps to solve equilibria problems. Note that in many problems steps 3 and 4 are obvious and can be skipped.

1. Write the balanced chemical reaction.
2. Determine the initial concentrations of the reactants and products.
3. Calculate the reation quotient, Q, to determine if the reaction will proceed in the forward or reverse directions to reach equilibrium.
4. Determine the change in reactant and product concentrations to reach equilibrium.
5. Write the equilibrium constant expression and solve for the unknown.

Sample Equilibria Problem

• gas-phase