Practice question

Given: In the Dumas method, 0.5 g of a compound gave 134.4 mL of N₂ at STP. What is the percentage of nitrogen? (Atomic mass: N = 14) These values define the system as per NCERT data. Formula: Mass of N₂ = 28 × 134.4/22400 = 0.168 g. This is standard NCERT relation. Substitution & Calculation: Mass of N = 0.168 g. Percentage = 0.168 × 100/0.5 = 33.6% . Result: The computed value matches expected outcome and confirms correct choice as per NCERT.