Practice question

Given: What is the pH of a 0.004 M Ca(OH)2 solution, assuming complete dissociation? These values define the system as per NCERT data. Formula: [OH-] = 2 × 0.004 = 0.008 M, pOH = -log(0.008) approx 2.1. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: pH = 14 - 2.1 = 11.9 . Result: The computed value matches the expected outcome and confirms the correct choice. Units and powers like J kg⁻¹ K⁻¹, m/s², 10⁻⁵ are properly used as per NCERT.