1. What is Equilibrium Constant at Equilibrium?

Definition: The equilibrium constant (K_c) is the value of its reaction quotient at chemical equilibrium, relating the concentrations of products and reactants at equilibrium.

Purpose: This calculator helps determine the equilibrium constant based on thermodynamic properties (enthalpy and entropy changes) at a given temperature.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( K_c \) — Equilibrium constant (dimensionless)
• \( \Delta H \) — Change in enthalpy (J/kg)
• \( \Delta S \) — Change in entropy (J/kg·K)
• \( T \) — Temperature (Kelvin)
• \( R \) — Universal gas constant (8.314 J/mol·K)

Explanation: The formula relates thermodynamic properties to the equilibrium position of a chemical reaction.

3. Importance of Equilibrium Constant

Details: The equilibrium constant is crucial for predicting reaction direction, extent of reaction, and understanding chemical systems at equilibrium.

4. Using the Calculator

Tips: Enter the change in enthalpy (ΔH), change in entropy (ΔS), and temperature in Kelvin. Temperature must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What does a large K_c value indicate?
A: A large K_c (>1) indicates the reaction favors product formation at equilibrium.

Q2: How does temperature affect K_c?
A: For endothermic reactions (ΔH > 0), K_c increases with temperature. For exothermic reactions (ΔH < 0), K_c decreases with temperature.

Q3: What units should I use for ΔH and ΔS?
A: Use consistent energy units (J/kg for ΔH and J/kg·K for ΔS) for accurate results.

Q4: Can K_c be negative?
A: No, equilibrium constants are always positive values.

Q5: What's the difference between K_c and K_p?
A: K_c uses concentrations while K_p uses partial pressures, but they're related through the ideal gas law.