How many liters of N2 are produced at STP?

Molar mass of NaN₃ = (23.0 + 14.0×3) g/mol = 65.0 g/mol

2NaN₃ → 2Na + 3N₂
Mole ratio NaN₃ : N₂ = 2 : 3
No. of moles of NaN₃ reacted = (148 g) / (65.0 g/mol) = 2.277 mol
No. of moles of H₂ produced = (2.277 mol) × (3/2) = 3.416 mol


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Method 1 :

Each mole of gas occupied a volume of 22.4 L at STP.
Volume of N₂ produced = (3.416 mol) × (22.4 L/mol) = 76.5 L


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Method 2 :

Gas law : PV = nRT
Volume of N₂ produced, V = nRT/P = 3.416 × 0.08206 × 273 / 1 L = 76.5 L