Question

10. (10 points) Sodium azide, NaNs, is used to provide gas to inflate automobile air bags. What mass of sodium azide is needed to provide the nitrogen needed to inflate a 70.0 L bag to a pressure of 1.3 atm at 25°C? 2 NaN3 (s) → 2 Na (s) + 3 N2(g)

Answer 1

we have:

P = 1.3 atm

V = 70.0 L

T = 25.0 oC

= (25.0+273) K

= 298 K

find number of moles using:

P * V = n*R*T

1.3 atm * 70 L = n * 0.08206 atm.L/mol.K * 298 K

n = 3.719 mol

This is number of moles of N2 required

Now from reaction,

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

=(2/3)*3.719 mol

= 2.479 mol

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

= 1*22.99 + 3*14.01

= 65.02 g/mol

we have below equation to be used:

mass of NaN3,

m = number of mol * molar mass

= 2.479 mol * 65.02 g/mol

= 161 g

Answer: 161 g

Feel free to comment below if you have any doubts or if this answer do not work