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Definition: This calculator determines the equilibrium constant (K₂) at a different temperature (T₂) given the equilibrium constant (K₁) at temperature T₁.
Purpose: It helps chemists and chemical engineers predict how equilibrium constants change with temperature using the van't Hoff equation.
The calculator uses the van't Hoff equation:
Where:
Explanation: The equation shows how the equilibrium constant changes with temperature when the enthalpy change is known.
Details: Understanding how equilibrium constants vary with temperature is crucial for reaction optimization, process design, and predicting reaction outcomes.
Tips: Enter K₁, ΔH (in J/mol), T₁ (initial temperature in Kelvin), and T₂ (final temperature in Kelvin). All values must be positive.
Q1: What is the range of valid temperatures?
A: Temperatures must be in Kelvin and greater than 0. Typical ranges are 200K-1000K for most chemical reactions.
Q2: How accurate is this calculation?
A: It assumes ΔH is constant over the temperature range. For large temperature differences, consider using temperature-dependent ΔH.
Q3: What units should be used for ΔH?
A: ΔH must be in Joules per mole (J/mol) for the calculation to work correctly with the gas constant.
Q4: Can I use Celsius instead of Kelvin?
A: No, the equation requires absolute temperatures in Kelvin. Convert Celsius to Kelvin by adding 273.15.
Q5: What does a higher K₂ value indicate?
A: A higher equilibrium constant at T₂ suggests the reaction favors products more at the higher temperature (for endothermic reactions).