Change in Entropy Formula:
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Definition: This calculator determines the change in entropy of a thermodynamic system using the Gibbs free energy, enthalpy change, and temperature.
Purpose: It helps in understanding the spontaneity and equilibrium of chemical reactions and physical processes.
The calculator uses the formula:
Where:
Explanation: The difference between enthalpy change and Gibbs free energy divided by the absolute temperature gives the entropy change.
Details: Entropy change helps predict whether a process will occur spontaneously and determines the efficiency of thermodynamic systems.
Tips: Enter the change in enthalpy (J/kg), Gibbs free energy (J), and temperature in Kelvin. Temperature must be > 0.
Q1: What does a negative entropy change mean?
A: A negative value indicates the system becomes more ordered during the process.
Q2: Why must temperature be in Kelvin?
A: The Kelvin scale is an absolute temperature scale required for thermodynamic calculations.
Q3: How is Gibbs free energy related to entropy?
A: Gibbs energy incorporates both enthalpy and entropy to determine process spontaneity at constant pressure and temperature.
Q4: What are typical units for these quantities?
A: Enthalpy change in J/kg, Gibbs energy in J, temperature in K, and entropy change in J/kg·K.
Q5: Can this be used for phase transitions?
A: Yes, this formula applies to any thermodynamic process including phase changes.