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⚖️ Equilibrium Constant Calculator

Calculate Kc, Kp, and predict reaction direction

Kc Calculator (Concentration)

Kp Calculator (Pressure)

Kc ⇌ Kp Conversion

Reaction Quotient (Q) & Direction

Equilibrium Constants Reference Guide

Key Formulas:

Kc = [Products]^coefficients / [Reactants]^coefficients

Kp = (P_products)^coefficients / (P_reactants)^coefficients

Kp = Kc(RT)^Δn

Equilibrium Interpretation:

K >> 1:

Products favored. Reaction goes nearly to completion.

K ≈ 1:

Neither side favored. Significant amounts of both.

K << 1:

Reactants favored. Little product formation.

Reaction Quotient (Q):

  • Q < K: Reaction shifts right (forward) to reach equilibrium
  • Q = K: System is at equilibrium
  • Q > K: Reaction shifts left (reverse) to reach equilibrium

Important Notes:

  • Pure solids and liquids are not included in K expressions
  • K is temperature dependent (changes with T)
  • Kp only applies to gas-phase reactions
  • When Δn = 0, Kp = Kc