Question

The relation between equilibrium constants \(K_C\) and \(K_P\) is:

• A. \(K_P = K_C(RT)^{\Delta n}\)
• B. \(K_P = K_C(RT)^{1/\Delta n}\)
• C. \(K_C = K_P(RT)^{\Delta n}\)
• D. \(K_C = K_P(RT)^{1/\Delta n}\)

Hint:

Remember: \(\Delta n = moles_{products} - moles_{reactants}\) for gases when converting between \(K_C\) and \(K_P\).

Answer 1

The Correct Option is A

Step 1: Defining KC and KP.
KC is the equilibrium constant expressed via concentrations (mol/L), while KP uses partial pressures (atm).

Step 2: Ideal gas relationship.
For a gaseous species, P = CRT, where C denotes molar concentration.

Step 3: Deriving KP from KC.
KP = Π (Pi)^νi = Π (Ci RT)^νi = KC (RT)^(Σ νi).

Step 4: Introducing Δn.
Δn = Σ ν(products) - Σ ν(reactants).

Step 5: Final expression.
KP = KC (RT)^Δn.

Step 6: Conclusion.
This represents the standard interconversion between KP and KC for gas-phase equilibria.