Answer: 4.5 moles of
can be made from complete reaction of 3.0 moles of Al.
Explanation:
The given reaction equation is as follows.

This shows that 2 moles of Al reacts with 6 moles of HCl. So, the amount of HCl required to react with 1 mole Al is three times the amount of HCl.
Therefore, 3 moles of Al will react with 9 moles of HCl to give 3 moles of
and
moles of
.
The reaction equation now will be as follows.

The moles
can also be written as 4.5 moles.
Thus, we can conclude that 4.5 moles of
can be made from complete reaction of 3.0 moles of Al.
Im not positive but i think it is When it is a gas?
describes what occurs every time in a given situation