If 30.2 g of aluminum react with HCI to produce aluminum chloride and hydrogen gas, how many liters of hydrogen are produced at STP?

1 Answer
Sep 10, 2016

Under #40*L# of dihydrogen gas are generated.

Explanation:

We must use a stoichiometric equation:

#Al(s) + 3HCl(aq) rarr AlCl_3(aq) +3/2H_2(g)uarr#

This equation tells us that #26.98*g# aluminum metal gives us #33.6*L# of dihydrogen gas. Why? Because #1# #mol# of gas occupies #22.4*L# at #"STP"# and #1.5*mol# were generated.

#"Moles of aluminum"# #=# #(30.2*g)/(26.98*g*mol^-1)# #=# #1.12*mol#.

Given the stoichiometry, #3/2xx1.12*cancel(mol)xx22.4*L*cancel(mol^-1)# are generated.