What is the significance of the standard Gibbs free energy change (G) in chemical reactions?

The standard Gibbs free energy change (ΔG°) in chemical reactions is significant because it determines whether a reaction is spontaneous or non-spontaneous under standard conditions (1 atm pressure, 298 K temperature, and 1 M concentration for all reactants and products).

If ΔG° < 0, the reaction is spontaneous, meaning it can proceed without external energy input.

If ΔG° > 0, the reaction is non-spontaneous, requiring external energy to proceed.

If ΔG° = 0, the system is at equilibrium, and no net reaction occurs.

This value is crucial for predicting the direction and feasibility of chemical reactions.