1. What is Equilibrium Temperature?

The equilibrium temperature (T_eq) is the temperature at which a chemical reaction reaches equilibrium, where the Gibbs free energy change (ΔG) equals zero. At this temperature, the forward and reverse reaction rates are equal.

2. How Does the Calculator Work?

The calculator uses the Gibbs free energy equation:

Where:

• \( T_{eq} \) — Equilibrium temperature (K)
• \( \Delta H \) — Enthalpy change (J)
• \( \Delta S \) — Entropy change (J/K)

Explanation: The equation calculates the temperature where the system is at equilibrium based on enthalpy and entropy changes.

3. Importance of Equilibrium Temperature

Details: Equilibrium temperature is crucial for predicting reaction spontaneity, designing chemical processes, and understanding phase transitions in thermodynamics.

4. Using the Calculator

Tips: Enter enthalpy change in joules (J) and entropy change in joules per kelvin (J/K). Ensure entropy change is not zero.

5. Frequently Asked Questions (FAQ)

Q1: What if ΔS is zero or negative?
A: If ΔS = 0, the equation is undefined. If ΔS < 0, the equilibrium temperature may indicate the reaction is spontaneous below this temperature.

Q2: How does this relate to Gibbs free energy?
A: At T_eq, ΔG = 0. Below T_eq, the reaction may be spontaneous in one direction; above T_eq, in the opposite direction.

Q3: What units should be used?
A: Consistent SI units are required: joules for energy and joules per kelvin for entropy.

Q4: Can this be used for phase transitions?
A: Yes, particularly useful for calculating melting, boiling, and sublimation temperatures.

Q5: What are typical values for equilibrium temperatures?
A: Varies widely depending on the system - from cryogenic temperatures to thousands of kelvins for different chemical reactions.