Which of the following is/are correct statement(s)? — Chemical Equilibrium Chemistry Question

💡 Solution & Explanation

(a) High pressure shifts the equilibrium CaCO₃(s) ⇌ CaO(s) + CO₂(g) backward, suppressing dissociation (correct). (b) PCl₅ ⇌ PCl₃ + Cl₂ produces more moles of gas, decreasing the average (apparent) molecular mass (correct). (c) Melting of ice decreases volume, so it is favored by high pressure, not low (incorrect). (d) Forming H₂ from H atoms is highly exothermic, so it is favored at low temperatures (incorrect). Therefore, correct answer is A,B.