The moles of oxygen required to react with 6.8 gram of ammoniaNH3+O2→NO+H2O( unbalanced ) is ____?

Balanced equation is 4NH3+5O2→4NO+6H2O  Therefore 4×17 gram of ammonia reacts with 5 moles of oxygen   Then 6.8 gram of ammonia react with (6.8×5)/17×4 mole of oxygen =0.5