Answer:
[tex]\boxed{ \text{18 mol}}[/tex]
Explanation:
(a) Balanced equation
4NH₃ + 3O₂ ⟶ 2N₂ + 6H₂O
(b) Calculation
You want to convert moles of NH₃ to moles of H₂O
The molar ratio is 6 mol H₂O:4 mol NH₃
[tex]\text{Moles of H$_{2}$O} =\text{12 mol NH$_{3}$} \times \dfrac{\text{6 mol H$_{2}$O}}{\text{4 mol NH$_{3}$}} = \textbf{18 mol H$_{2}$O}\\\\\text{The reaction will produce }\boxed{ \textbf{18 mol of H$_{2}$O}}[/tex]