J.R. S. answered 03/04/19
Tutor
5.0
(145)
Ph.D. University Professor with 10+ years Tutoring Experience
Assuming complete reaction you have
4NH3 + 7O2 ==> 4NO2 + 6H2O
6.78 L NH3 x 7 L O2/4 L NH3 = 11.9 L (3 sig figs)