Why concentration of pure liquid and solid are excluded from the equilibrium constant expression?

The concentrations of pure solids, pure liquids, and solvents are omitted from equilibrium constant expressions because they do not change significantly during reactions when enough is present to reach equilibrium.

How can Nernst equation be applied in calculating the equilibrium constant for any cell reaction?

Determining Equilibrium Constant with Nernst Equation When the reactants and the products of the electrochemical cell reach equilibrium, the value of ΔG becomes 0. At this point, the reaction quotient and the equilibrium constant (Kc) are the same. Since ΔG = -nFE, the cell potential at equilibrium is also 0.

What is equilibrium constant in Nernst equation?

The Nernst equation calculates electrochemical cell potential from standard cell potential, the gas constant, absolute temperature, number of moles of electrons, Faraday’s constant, and the reaction quotient. At equilibrium, the reaction quotient is the equilibrium constant.

Why the concentration of pure liquid and solid are constant?

That is because the density of liquids and solids is temperature and pressure dependent. The reason that the molar concentration is often called constant is twofold: the density of liquids and solids has a much weaker dependence on the temperature than gases do therefore it can be regarded as approximately constant.

Does equilibrium constant include aqueous?

Kc is in terms of concentration, so will include aqueous species, mixture of liquids and gases. For Kp we only include the partial pressure of gases, so only partial pressure of B, PB , will be included.

Why does change in concentration not affect KC?

⇒ Catalysts lower Ea for the reaction, so a catalyst decreases the amount of time taken to reach equilibrium for both the forward and reverse reactions. ⇒ The catalyst does not affect the equilibrium concentrations of reactants and products in the equilibrium mixture; thus, the Kc value does not change.

Why is the Nernst equation important?

Importance of Nernst Equation The Nernst Equation allows for cell potential determination under non – standard conditions. It relates the measured cell potential to the quotient of the reaction and allows the exact determination of constants of equilibrium (including constants of solubility).

Why is Nernst equation used?

The Nernst Equation enables the determination of cell potential under non-standard conditions. It relates the measured cell potential to the reaction quotient and allows the accurate determination of equilibrium constants (including solubility constants).