For a spontaneous process at constant T and P, the Gibbs free energy change (ΔG) must be ________.
- Positive
- Negative
- Zero
- Infinite
Answer: Negative
ΔG = ΔH - TΔS. If ΔG < 0, process is spontaneous; ΔG > 0, non-spontaneous; ΔG = 0, equilibrium. Unifies enthalpy and entropy for predicting reaction feasibility. [[NCERT Chemistry Class 11]]