Question

in a chemical reaction, transition - state molecules are formed by the binding of substrate to enzyme. in an exergonic reaction, products have free energies that are - lower than the reactants, but the same as the transition state molecules. lower than either the reactants or the transition state molecules. lower than the reactants, but higher than the transition state molecules. higher than the reactants, but lower than the transition state molecules. higher than either the reactants or the transition state molecules.

Explanation:

1. In an exergonic reaction, the Gibbs free energy change ($\Delta G$) is negative, meaning products have less free energy than reactants.
2. The transition - state (activated complex) has the highest free energy in the reaction pathway (it's the peak of the energy curve).
3. So products' free energy is lower than both reactants (since $\Delta G<0$ for exergonic) and transition - state molecules (as transition state is the highest energy point).

Answer:

B. lower than either the reactants or the transition state molecules.