1. What is Gibbs Free Energy Change?

Definition: Gibbs free energy (ΔG) is a thermodynamic potential that measures the maximum reversible work that may be performed by a thermodynamic system at constant temperature and pressure.

Purpose: It helps predict whether a process will occur spontaneously at constant pressure and temperature.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \Delta G \) — Change in Gibbs free energy (Joules)
• \( w \) — Electrochemical work done by the system (Joules)

Explanation: The negative sign indicates that the free energy of the system decreases when work is done by the system on the surroundings.

3. Importance of Gibbs Free Energy

Details: Gibbs free energy is crucial in electrochemistry, chemical thermodynamics, and predicting reaction spontaneity. A negative ΔG indicates a spontaneous process.

4. Using the Calculator

Tips: Enter the electrochemical work done by the system in Joules. The calculator will compute the corresponding change in Gibbs free energy.

5. Frequently Asked Questions (FAQ)

Q1: Why is there a negative sign in the formula?
A: The negative sign indicates that when the system does work on its surroundings, its free energy decreases.

Q2: What are typical values for electrochemical work?
A: Values vary widely depending on the system, but common electrochemical cells might have work values from a few Joules to several kJ.

Q3: How does this relate to cell potential?
A: For electrochemical cells, ΔG = -nFE, where n is moles of electrons, F is Faraday's constant, and E is cell potential.

Q4: What does a positive ΔG indicate?
A: A positive ΔG means the process is non-spontaneous under the given conditions.

Q5: Can this be used for non-electrochemical systems?
A: Yes, the relationship ΔG = -w applies to any reversible work done at constant temperature and pressure.