Answer :
0.3 moles of Oxygen is excess reactant (reagent) when yield is 100% .
NO =5.6 moles
O2= 3.1 moles
2NO + O2 --> 2NO2 the chemical reaction.
the ratio of NO and O2 is 2:1
therefore for 5.6 moles of NO, 2.8 moles of Oxygen(O2) is required. So 3.1moles - 2.8 moles = 0.3 moles
The reactant in a chemical reaction that is present in a quantity that is larger than what is required to fully react with the limiting yield is known as the excess reactant. The substance(s) still present after a chemical reaction has reached equilibrium in yield are the reactant(s). Subtract the mass of excess reagent eaten from the total mass of excess reagent provided to determine the quantity of yield that is still present. Reactants in a chemical reaction are referred to as excess reagents if they are still present after the reaction is complete.
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