Answer:
We need 6.0 moles of aluminium
Explanation:
Step 1: Data given
Number of moles of H2 = 9.0 moles
Step 2: The balanced equation
2 Al + 6 HCl → 2 AlCl3 + 3H2
Step 3: Calculate moles Al
For 2 moles Aluminium, we need 6 moles HCl to produce 2 moles AlCl3 and 3 moles H2
For 9.0 moles of H2 we need 2/3 * 9.0 = 6.0 moles of aluminium
We need 6.0 moles of aluminium