Answer:
The amount in grams of aluminum chloride that can theoretically be formed from the 84 g of HCl and 30.8 g aluminium is 102.4 grams
Step-by-step explanation:
Aluminum metal reacts with hydrochloric acid to form aluminum chloride according to the reaction below. If 30.8 grams of aluminum react with 84 grams of HCl, how many grams of aluminum chloride can theoretically be formed? 2Al + 6HCl --> 2AlCl3 + 3H2
Hydrochloric acid / Molar mass
36.46 g/mol
Aluminium chloride / Molar mass
133.34 g/mol
Aluminium / Atomic mass
26.981539
Hydrogen / Atomic mass
1.00784 u
Number of moles of aluminium = mass/molar mass = 30.8 g/ 26.98 g/mol
= 1.142 moles.
Number of moles of HCl = mass/molar mass = 84/36.46 = 2.303 moles
From the reaction, 2 moles of Al react with 6 moles of HCl, therefore, 1.142 moles of aluminium react with (1.142 × 6/2) moles or 3.425 moles of HCl. Since the calculated number of moles of required HCl is more than the available moles, then HCl is the limiting reagent.
6 moles of HCl react with 2 moles of aluminium, then 2.303 moles will react with (2/6×2.303) or 0.76796 moles of aluminium to produce 0.76796 moles of aluminum chloride
Therfore mass of aluminum chloride produced = (Number of moles of aluminium chloride produced) × (molar mass of aluminium chloride)
0.76796 moles × 133.34 g/mol = 102.4 g