1. What is Gibbs Free Energy?

Definition: Gibbs Free Energy 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:

• \( G \) — Gibbs Free Energy (Joules)
• \( \Delta H \) — Change in Enthalpy (Joules)
• \( T \) — Temperature (Kelvin)
• \( \Delta S \) — Change in Entropy (Joules/Kelvin)

Explanation: The formula calculates the energy available to do work by considering both enthalpy changes and entropy changes at a given temperature.

3. Importance of Gibbs Free Energy

Details: Negative Gibbs free energy indicates a spontaneous process, while positive values indicate non-spontaneous processes. Zero means the system is at equilibrium.

4. Using the Calculator

Tips: Enter the change in enthalpy in Joules, temperature in Kelvin, and change in entropy in Joules/Kelvin. The calculator will compute the Gibbs free energy.

5. Frequently Asked Questions (FAQ)

Q1: What does a negative Gibbs free energy mean?
A: A negative value indicates that the process is thermodynamically favorable and will occur spontaneously under constant temperature and pressure.

Q2: What are typical units for Gibbs free energy?
A: The SI unit is Joules (J), though kilojoules (kJ) are also commonly used.

Q3: How does temperature affect Gibbs free energy?
A: Higher temperatures increase the influence of entropy changes on the Gibbs free energy calculation.

Q4: What's the relationship between Gibbs free energy and equilibrium?
A: When Gibbs free energy is minimized (ΔG = 0), the system is at equilibrium.

Q5: Can Gibbs free energy predict reaction rates?
A: No, it only indicates thermodynamic favorability, not kinetic factors like reaction rates.