Practice question

Given: The K_{sp of FeCO₃ is 3.1 × 10⁻¹¹. What is its solubility in water? These values define the system as per NCERT data. Formula: FeCO₃(s) <=> Fe²+ + CO₃²-, K_{sp = S². This is standard NCERT relation. Substitution & Calculation: S² = 3.1 × 10⁻¹¹, S = sqrt3.1 × 10⁻¹¹approx 5.57 × 10⁻⁶M. Result: The computed value matches expected outcome and confirms correct choice as per NCERT.