CuSO₄·5H₂O(s) ⇌ CuSO₄·3H₂O(s) + 2H₂O(g), K_p for this equilibrium is 1.0 × 10⁻⁴ atm² at 25°C. What i — Chemical Equilibrium Chemistry Question

💡 Solution & Explanation

From the given equilibrium, K_p = P_H₂O². So, P_H₂O = √(1.0 × 10⁻⁴) = 1.0 × 10⁻² atm = 0.01 atm. Converting to mm Hg: 0.01 atm × 760 mm/atm = 7.60 mm. The salt effloresces if the atmospheric vapour pressure is below this equilibrium value. Therefore, correct answer is A.