How many liters of hydrogen gas at STP can be generated from the reaction of excess hydrogen chloride (aka. hydrochloric acid) with 54.5 g of aluminum?

Answer 1

The balanced reaction: 2 Al + 6 HCl --> 2 Al Cl₃ + 3 H₂.

(54.5g Al) * (1 mol Al / 27.0g Al) * (3 mol H₂ / 2 mol Al) * (22.4 L / 1 mol gas at STP) = 67.8 L H₂ gas.