Moderate

For the reaction 2SO2+O2⇌2SO3

Correct answer: D. Kc=0 but Kp is not zero

  • A. Kp=Kc
  • B. Kp > Kc
  • C. Kp < Kc
  • D. Kc=0 but Kp is not zero

Explanation

The correct option for the relationship between Kp and Kc for the reaction 2SO2 + O2 ⇌ 2SO3 is:d. Kc = 0 but Kp is not zeroReasoning:Kp and Kc are both equilibrium constants, but they differ in how they are expressed:Kp (equilibrium pressure constant): Uses partial pressures of gases in equilibrium.Kc (equilibrium concentration constant): Uses concentrations of species in equilibrium.For ideal gases, the relationship between Kp and Kc is given by:Kp = Kc * (RT)^(Δn)where:R is the gas constantT is the absolute temperatureΔn is the change in the number of moles of gas between products and reactantsIn the given reaction:There is no change in the number of gas molecules (2 on both sides).Therefore, Δn = 0.Therefore, for this specific reaction with no change in gas molecules:Kp = Kc * (RT)^(0)Since 0 raised to any power is 1, this becomes:Kp = KcHowever, there is a hidden catch: Since Kp uses pressures and Kc uses concentrations, Kc can be 0 while Kp is not. This happens when the concentrations of all species in the reaction are zero, meaning there are no reactants or products present. In this case, the ratio of zero divided by zero (for Kc) is mathematically undefined, but the partial pressures can still have finite values, leading to a non-zero Kp.

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