What is Gibbs free energy and why is it significant in predicting the spontaneity of chemical reactions?

• A. Gibbs free energy is the energy available to perform work, and it predicts the spontaneity of reactions by indicating whether a reaction will proceed without external input.
• B. Gibbs free energy is the energy stored in chemical bonds, and it predicts the spontaneity of reactions by indicating the stability of reactants.
• C. Gibbs free energy is the total energy of a system, and it predicts the spontaneity of reactions by indicating the amount of heat released.
• D. Gibbs free energy is the kinetic energy of molecules, and it predicts the spontaneity of reactions by indicating the speed of reaction.

Answer: (A)