Question

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.
a. 76.3 g
b. 42.8 g
c. 38.7 g
d. 62.7 g

Answer 1

See the post on limestone. All of these stoichiometry problems are worked the same way.

Answer 2

=38.7 g (c)

Steps
20/22.4= 0.89 mols of NaN3
Balanced Equation
2(NaN3) --> 2(Na) + 3(N2)
Looking for mols of n2
So 2(0.89)/3= mols of n2 =0.59 mol
Then molar mass of NaN3 = 65
0.59x65= 38.7 g