Equilibrium Constant Formula:
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The equilibrium constant (Kc) quantifies the ratio of product concentrations to reactant concentrations at equilibrium, each raised to the power of their stoichiometric coefficients. It indicates the extent of a chemical reaction at equilibrium.
The calculator uses the equilibrium constant formula:
Where:
Explanation: The equation shows that Kc is the product of product concentrations (each raised to their coefficient) divided by the product of reactant concentrations (each raised to their coefficient).
Details: Kc helps predict reaction direction, extent of reaction, and how changes in conditions affect equilibrium. Large Kc values favor products, small values favor reactants.
Tips: Enter concentrations in mol/L and coefficients as whole numbers. Separate multiple values with commas. For example, for the reaction 2A ⇌ B + 3C, enter reactant concentration as "0.5" and coefficient as "2"; products as "0.1,0.3" and coefficients as "1,3".
Q1: What units does Kc have?
A: Kc is technically unitless, but its numerical value depends on the concentration units used (typically mol/L).
Q2: How does temperature affect Kc?
A: Kc changes with temperature. Exothermic reactions have Kc decrease with temperature increase, endothermic reactions have Kc increase.
Q3: What if solids or pure liquids are in the reaction?
A: Their concentrations are constant and not included in Kc expressions.
Q4: What does Kc = 1 mean?
A: At equilibrium, product and reactant concentrations are balanced (but not necessarily equal).
Q5: How is Kc different from Kp?
A: Kc uses concentrations (mol/L), while Kp uses partial pressures (atm) for gas-phase reactions.