Question

Air bags are activated when a severe impact causes a steel ball to compress a spring and electrically ignite a detonator cap. This causes sodium azide () to decompose explosively according to the following reaction: What mass of must be reacted to inflate an air bag to 72.0 L at STP?

Answer 1

Answer:

the mass required to inflate a 72 L bag is 191.491 g

Explanation:

reaction:

• 2 NaN3 ↔ 2 Na + 3 N2

conditions:

• V = 72.0 L
• STP: P = 1 atm  ∧ T = 298 K

gas law:

• PV = RTn
• R = 0.082 atm * L / K * mol

⇒ n = PV / RT

⇒ n = ((1 atm) * ( 72.0 L)) / (0.082 atm*L / K*mol) * (298 K)

⇒ n = 2.946 mol

⇒ m = n * Mw = ( 2.946 mol ) * ( 64.99 g/mol)

⇒ m = 191.491 g