Practice question

Given: What is the mass percentage of a solution formed by mixing 120 g of a 20% (w/w) solution with 180 g of a 10% (w/w) solution? Formula: Mass of solute from first = 0.20 × 120 = 24 g. Substitution & Calculation: Mass of solute from second = 0.10 × 180 = 18 g . Total solute = 24 + 18 = 42 g. Total mass = 120 + 180 = 300 g. Mass % = 42/300 × 100 = 14% . Final Result: The computed value matches expected outcome and confirms correct choice as per latest NCERT 2026-27.