Question

When sensors in a car detect a collision, they cause the reaction of sodium azide, NaN3, which generates nitrogen gas to fill the air bags within 0.03 s. How many liters of N2 are produced at STP if the air bag contains 148 g of NaN3? Express your answer with the appropriate units.

Answer 1

Molar mass of NaN3 = 1*MM(Na) + 3*MM(N)

= 1*22.99 + 3*14.01

= 65.02 g/mol

mass of NaN3 = 148 g

mol of NaN3 = (mass)/(molar mass)

= 148/65.02

= 2.2762 mol

we have the Balanced chemical equation as:

2NaN3 ---> 3N2 + 2 Na

From balanced chemical reaction, we see that

when 2 mol of NaN3 reacts, 3 mol of N2 is formed

mol of N2 formed = (3/2)* moles of NaN3

= (3/2)*2.2762

= 3.4143 mol

At STP, volume of 1 L of gas = 22.4 L

So,

volume = number of mol*molar volume

= 3.4143 * 22.4 L

= 76.5 L

Answer: 76.5 L