Chemistry Problem?!?

Question

How do you solve this?

You are asked to design an air bag for a car. You know that the bag should be filled with gas having a pressure higher than atmospheric pressure, say 829 mm Hg, at a temperature of 22.0OC. The bag has a volume of 45.5L. What quantity of sodium azide, NaN¬3 should be used to generate the required quantity of gas? The gas producing reaction is :

NaN3 (s) Na(s) + N2 (g)

Answer 1

PV=NRT

The Amateur would convert to grams first.