Aluminum sulphate is used in finishing paper, among other uses. If 500 kg of aluminum oxide dihydrate react completely with 1500 kg of 90% by mass aqueous H₂SO₄, how many kg of aluminum sulphate can be produced?
Al₂O₃ •2H₂O + 3H₂SO₄ $\rarr$ Al₂(SO₄) ₃ + 5H₂O

Question

Aluminum sulphate is used in finishing paper, among other uses. If 500 kg of aluminum oxide dihydrate react completely with 1500 kg of 90% by mass aqueous H₂SO₄, how many kg of aluminum sulphate can be produced?
Al₂O₃ •2H₂O + 3H₂SO₄

\rarr

Al₂(SO₄) ₃ + 5H₂O

Quizplus · Accepted Answer

The balanced chemical equation is:Al₂O₃ •2H₂O + 3H₂SO₄ $\rarr$ Al₂(SO₄)₃ + 5H₂OFrom the equation, we see that 1 mole of Al₂O₃ •2H₂O reacts with 3 moles of H₂SO₄ to produce 1 mole of Al₂(SO₄)₃.The molar mass of Al₂O₃ •2H₂O is 156 g/mol, and the molar mass of Al₂(SO₄)₃ is 342 g/mol.Therefore, 500 kg of Al₂O₃ •2H₂O is equal to 500 kg / 156 g/mol = 3205 mol.1500 kg of 90% by mass aqueous H₂SO₄ is equal to 1500 kg * 0.9 = 1350 kg of H₂SO₄.1350 kg of H₂SO₄ is equal to 1350 kg / 98 g/mol = 13780 mol.Since 3 moles of H₂SO₄ react with 1 mole of Al₂O₃ •2H₂O, we have 13780 mol / 3 = 4593 mol of H₂SO₄ available to react with Al₂O₃ •2H₂O.Therefore, the limiting reactant is Al₂O₃ •2H₂O, and the maximum amount of Al₂(SO₄)₃ that can be produced is 3205 mol.3205 mol of Al₂(SO₄)₃ is equal to 3205 mol * 342 g/mol = 1.10 x 10⁶ g = 1.10 x 10³ kg.Therefore, the correct answer is A) 1.24 x 10³kg.

Aluminum Sulphate Is Used in Finishing Paper, Among Other Uses →\rarr→

Aluminum Sulphate Is Used in Finishing Paper, Among Other Uses $\rarr$