Kp = Kc (RT)△n in the equation if △n < 0 then:
Correct answer: B. Kp < Kc
- A. Kp = Kc
- B. Kp < Kc
- C. Kp > Kc
- D. Kp < 0
Explanation
Kp and Kc are equilibrium constants for reactions involving gases. Kp is used when partial pressures are involved, while Kc is used for molar concentrations. The relationship between them is given by the equation Kp = Kc (RT)△n, where △n is the change in moles of gases. When △n < 0, it implies that the number of moles of gaseous products is less than the number of moles of gaseous reactants, making (RT)△n a fraction. Thus, Kp < Kc. Option B is correct. Option A is valid when △n = 0, making Kp = Kc. Option C occurs when △n > 0, which makes Kp > Kc. Option D is incorrect as equilibrium constants cannot be negative.
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