J.R. S. answered 01/23/19
Ph.D. University Professor with 10+ years Tutoring Experience
O2 will be limiting. You can tell this by dividing the liters of each by thei coefficient in tge balanced equation.
For NH3 you have 3.0 L/4 = 0.75
For O2 you have 3.0 L/5 = 0.6
0.6 < 0.75 so O2 is limiting.
Max volume of NO = 3.0 L O2 x 4 L NO/5 L O2 = answer