Question

In a collision of sufficient force, automobile air bags respond by electrically triggering the explosive decomposition of sodium azide (NaN3) to its elements. A 29.4−g sample of sodium azide was decomposed, and the nitrogen gas generated was collected over water at 26°C. The total pressure was 733.8 mmHg. How many liters of dry N2 were generated?

Answer 1

2NaN₃ = 2Na + 3N₂

M(NaN₃) - 65 g/mol; n(NaN₃) = 29.4/65= 0.452 mol; n(N₂) = 3/2 n(NaN₃)= 0.678 mol

PV=nRT

1 mm Hg = 133.3 Pa, 733.8 mmHg= 97815.54 Pa= 97.815 kPa;

V = nRT/P = 0.678 * 8.314 * (273.15 + 26) / 97.815 = 17.24 liters of N₂