Practice question

Given: In combustion analysis, 0.36 g of a compound gave 0.36 g of H₂O . What is the percentage of hydrogen? (Atomic masses: H = 1, O = 16) These values define the system as per NCERT data. Formula: Molar mass of H₂O = 18 g/mol. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: Mass of H = 2 × 0.36/18 = 0.04 g. Percentage = 0.04 × 100/0.36 = 11.11% . 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.