In the reaction, 4NH3g +  5O2g  →  4NOg  +  6H2O g, when 1 mole of ammonia and 1 mole of O2 are made to react to completion

4NH3g +  5O2g  →  4NOg  +  6H2O g        4moles      5molesgiven  1mole        ?       number of moles of O2 required = 54>1But given no.of moles of Oxygen= 1So O2 is Limiting reagent & it consumes completelyFrom equation,   5moles ofO2→4 moles of NO + 6 moles of H2O   1 mole        →        ?                            ? nNO = 45=0.8     ;    nH2O= 65=1.2  5 moles of O2 react with 4 moles of NH31 mole of  O2   react with       ?nNH3=45=0.8nNH3left = 1-0.8 =0.2