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Kc to Kp Conversion:
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The Kc to Kp conversion relates the equilibrium constant in terms of concentration (Kc) to the equilibrium constant in terms of partial pressures (Kp). This conversion is essential in gas-phase equilibria where measurements can be made in different units.
The calculator uses the conversion formula:
Where:
Explanation: The equation accounts for the relationship between concentration and pressure in gas-phase reactions, with the exponent reflecting the stoichiometric change in gas moles.
Details: Kp is particularly important when working with gas-phase equilibria where partial pressures are more easily measured than concentrations. It's essential for predicting reaction directions and understanding equilibrium positions under different conditions.
Tips: Enter Kc (must be positive), temperature in Kelvin (must be positive), and Δn (can be positive, negative, or zero). The calculator will compute Kp, which is dimensionless.
Q1: What's the difference between Kc and Kp?
A: Kc uses molar concentrations while Kp uses partial pressures. They're related through the ideal gas law and differ when Δn ≠ 0.
Q2: When is Kp equal to Kc?
A: When Δn = 0 (same number of gas moles on both sides of the equation), Kp = Kc since (RT)^0 = 1.
Q3: What units should I use for temperature?
A: Temperature must be in Kelvin for this calculation. Convert from Celsius by adding 273.15.
Q4: Can Δn be negative?
A: Yes, Δn is negative when there are fewer moles of gas products than reactants.
Q5: Why is R = 0.0821 in this equation?
A: This specific value of R (in L·atm/mol·K) ensures unit consistency when converting between concentration and pressure.