Steve,

 

Hello. I am kind of stuck on this one... could you help?  Not sure which gas law applies?

 

As always, Thanks!

 

A 3.05 g sample of ammonium nitrate is introduced into an evacuated 2.18 L flask and then heated to 250 ºC.  What is the total gas pressure, in atmospheres, in the flask at 250 ºC when the ammonium nitrate has completely decomposed?

NH₄NO₃ (s) �?N₂O (g) + 2 H₂O (g)