NH3(g)+?O2(g)→?NO(g)+?H2O(g) What volume of H2O(g) is produced by the reaction under the same conditions

Answer 1

They are asking you to balance the equation:

4NH3(g) + 5O2(g) ==> 4NO(g) + 6H2O(g) ... balanced equation

So, for every liter of NH3 that reacts, 1.5 liters of H2O are produced