Automobile air bags employ a chemical reaction involving the rapid decomposition of sodium azide (NaN₃) into sodium metal and nitrogen gas to inflate in a collision. How much sodium azide is required to decompose to inflate a 20.0 L air bag? Assume that the gas is at standard temperature and pressure, and thus occupies 22.4 L per mole.

Question

Quizplus · Accepted Answer

At STP, 1 mole of gas occupies 22.4 L. To inflate a 20.0 L air bag, approximately 0.893 moles of nitrogen gas are needed. The balanced equation for the decomposition of sodium azide is 2 NaN₃ → 2 Na + 3 N₂, indicating that 2 moles of NaN₃ produce 3 moles of N₂. Therefore, 0.893 moles of N₂ require 0.595 moles of NaN₃. The molar mass of NaN₃ is 65 g/mol, so 0.595 moles of NaN₃ weigh approximately 38.7 g.

Automobile Air Bags Employ a Chemical Reaction Involving the Rapid