Answer:
44.4 moles of NH3.
Explanation:
You can see in the chemical equation that 4 moles of NH3 reacted produces 6 moles of H2O. We want to know how many moles we need to produce 66.6 moles of H2O. To do this, we state a rule of three:
[tex]\begin{gathered} 4\text{ moles NH}_3\rightarrow6\text{ moles H}_2O \\ ?\text{ moles NH}_3\rightarrow66.6\text{ moles H}_2O. \end{gathered}[/tex]And the calculation from this rule of three will be:
[tex]66.6\text{ moles H}_2O\cdot\frac{4_\text{ moles NH}_3}{6\text{ moles H}_2O}=44.4\text{ moles NH}_3.[/tex]We will need 44.4 moles of NH3 to produce 66.6 moles of H2O.