Answer:
7 moles
Explanation:
The balanced equation for the reaction is given below:
6NaOH + 2Al —> 2Na3AlO3 + 3H2
The number of moles of NaOH required to produce 3.5 moles of hydrogen, H2 can be obtaine as follow:
From the balanced equation above, 6 moles of NaOH reacted to produce 3 moles of H2.
Therefore, Xmol of NaOH will react to produce 3.5 moles of NaOH.
Xmol of NaOH = (6 x 3.5)/3
Xmol of NaOH = 7 moles
Therefore, 7 moles of NaOH are required.