What mass of sodium azide, NaN3, is needed to fill a 85.0L air bag of a compact car upon collision assuming the barometric pressure is 29.5 in Hg and the temp. is 75.0'F?
NaN3 ------> 2 Na(s) +3 N2(g)

for perfect gases (I assume you can make the assumption that N2 approximates a perfect gas): PV = nRT

You have all the data you need to work out mass of NaN3 needed.

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