# Lesson Worksheet: Equilibrium Constants and Gibbs Free Energies Chemistry • 10th Grade

In this worksheet, we will practice converting between Gibbs free energies of equilibria and equilibrium constants by applying the equation ΔG = –RTlnK.

Q1:

Which of the following is the best definition of , the standard change in Gibbs free energy for a reversible process?

• A is the difference in free energy between the pure products in their stoichiometric ratio and the equilibrium mixture of reactants and products.
• BWhen the concentrations or partial pressures of reactants and products are all equal to the standard value, is the energy that must be absorbed for equilibrium to be reached.
• C is the difference in free energy between the pure reactants in their stoichiometric ratio and the equilibrium mixture of reactants and products.
• DWhen the concentrations or partial pressures of reactants and products are all equal to the standard values, is the energy that must be released for equilibrium to be reached.
• EWhen the sum of the concentrations or partial pressures of reactants and products is equal to the standard value, is the energy that must be released for equilibrium to be reached.

Q2:

The standard change in Gibbs free energy for a reversible process, , is measured for a standard solution of reactants and products. What are the initial concentrations of the reactants and products in this solution?

• AReactants are present in the stoichiometric ratio and the sum of the reactant concentrations is 1 M. Product concentrations are defined in the same way.
• BReactants and products are present in the stoichiometric ratio and the sum of the reactant concentrations is 1 M.
• CReactants and products are present in the equilibrium ratio and the sum of the reactant and product concentrations is 1 M.
• DThe concentration of each reactant and product is 1 M.
• EReactants and products are present in the stoichiometric ratio and the sum of the reactant and product concentrations is 1 M.